An Intellectual diaspora

Heinz Thannhauser did his post graduate studies at Harvard, under Professor Wilhelm Koehler , a German emigre who had arrived at Harvard in 1934. In intellectual terms , Koehler could trace his roots back to the Vienna School of Art History , and he was only one of a distinguished diaspora of art historians from Germany  who did the same. Many of them were Jewish , although some were not being involved with the modern art despised by Hitler and the Nazis. Without the refuge provided to them by Britain and particularly the United States,  the discipline of art history would have been much diminished. Since many of the exiles ended up in Boston and at Harvard, it is tempting to speculate that Thannhauser may have met with them while he studied at Harvard. 

Rather than just being a physical place, The Vienna School of Art History (Wiener Schule der Kunstgeschichte) was an intellectual evolution of art history extending over a number of generations, in which a series of outstanding scholars each built upon the achievements of their forerunners, while contributing their own unique perspectives. The Vienna School attempted to put art history on a "scientific" ("wissenschaftlich") basis by distancing art historical judgements from questions of aesthetic preference and taste, and by establishing rigorous concepts of analysis through which all works of art could be understood. The term gained general currency following articles published by Otto Benesch in 1920 and by Julius von Schlosser in 1934 Rudolf Eitelberger is considered to have been the founder of the Vienna School. The first graduate of the Eitelberger's new program in art history was Moritz Thausing, who in 1879 became the second Ordinarius (full professor) of art history at Vienna. He advocated an autonomous art history which promoted the separation of art history from aesthetics.  Thausing's students Franz Wickhoff (Professor 1891) and Alois Riegl (Professor 1897) furthered his approach, which developed methods of comparative stylistic analysis attempting to avoid judgements of personal taste. Riegl and Wickhoff,  were succeeded by Max Dvořák, who at first continued the tradition of his predecessors. However, his interests gradually turned towards issues of content. Dvořák, in part influenced by the contemporary expressionist movement in German painting, developed a deep appreciation for the unclassical formal qualities of Mannerism. Dvořák's idealistic method, which would later be termed "Kunstgeschichte als Geistesgeschichte" ("art history as intellectual history"), found its most committed champions in Hans Tietze and Otto Benesch. Riegl and Wickhoff had died relatively young and Dvořák shared their fate, dying at the early age of .. in  

In 1922 Julius von Schlosser was appointed as his successor. He was a classical, humanistic scholar with a deep attachment to the art and culture of Italy. He was a close friend of the Italian philosopher Benedetto Croce and of Karl Vossler, a Munich-based professor of the Romance languages, under whose influence he developed an art-historical method based on philological models. He drew a distinction between the "Stilgeschichte" ("style-history") of brilliant artists and their unique creations, and the "Sprachgeschichte" ("language-history") of the fine arts, which latter embraced the entire spectrum of artistic creation. Among those to emerge from Schlosser's school, were Ernst Gombrich, Hans Sedlmayr and Otto Pächt, who in the 1930s founded art-historical "structuralism." Their methodology was described by Meyer Schapiro as the "New Vienna School" .

The son of a Jewish lawyer, Hans Tietze grew up in Prague in a German speaking environment. In 1893, his family moved to Vienna. From 1900 to 1903, he studied archaeology, history and art history under Alois Riegl, Julius von Schlosser and Franz Wickhoff . In 1903, he completed his Ph.D. dissertation, supervised by Wickhoff, on the topic of medieval typological representation. In 1905, he wrote his Habilitationsschrift on Annibale Carracci's frescos at the Palazzo Farnese. In 1905, he married fellow art-history student Erika Conrat. For some time, he was Wickhoff's assistant at Vienna's first art historical institute chaired by Josef Strzygowski. He also became an assistant and secretary at the Commission for Monument Preservation. In 1909, he was appointed lecturer in art history at the University of Vienna. After World War I he became assistant professor and began editing the art journal, Die bildenden Künste. In 1913, he published his Methode der Kunstgeschichte, which "attempted to summarize the basic principles of the evolutionist methodological project developed by Wickhoff , Riegl and Max Dvořák. From 1923 to 1925, Tietze helped reorganizing Vienna's traditional art museum system into a more popular and pedagogical one.

One of Tietze and von Schlosser’s students was Ernst Gombrich was born, into an assimilated bourgeois family of Jewish origin in Vienna who were part of a sophisticated social and musical milieu. His father was a lawyer and and his mother was a distinguished pianist who graduated from the Vienna Conservatoire with the School's Medal of Distinction,  who had been a pupil of amongst others, Anton Bruckner. Gombrich was educated at the Theresianum and at the University of Vienna, where he studied art history under Tietze, Von Schlosser and Karl Maria Swoboda and Josef Strzygowski, completing a PhD thesis on the Mannerist architecture of Giulio Romano, supervised by Von Schlosser. Specialised in caricature, he was invited to help Ernst Kris, who was then keeper of decorative arts at the Kunsthistorisches Museum, on his graduating in 1933. After publishing his first book A Little History of the World in German in 1936, written for children and adolescents, and seeing it become a hit only to be banned by the Nazis for pacifism, he fled to Britain in 1936 to take up a post as a research assistant at the Warburg Institute, University of London. During World War II, Gombrich worked for the BBC World Service, monitoring German radio broadcasts. When in 1945 an upcoming announcement was prefaced by the Adagio of Bruckner's seventh symphony, h, Gombrich guessed correctly that Hitler was dead and promptly broke the news to Churchill 

Ernst Kris, Gombrich's colleague at the Kunsthistorisches Museum , also studied art history under Dvořák and von Schlosser receiving his doctorate in 1922. Kris was primarily a psychoanalyst, but also worked as an art historian and published articles on art history. As a psychoanalyst, he made some important contributions to the psychology of the artist and the psychoanalytic interpretation of works of art. In 1927 Kris married Marianne Rie, the daughter of a friend of  Sigmund Freud. They had two children. Kris and his wife both became psychoanalysts and Kris began to publish psychoanalytic papers.In 1928, Kris intensified his working relationship with Freud, and he became a member of the Vienna Psychoanalytic Society, working as a lecturer at the Vienna Psychoanalytic Institute. In 1936 he published a paper relating art to psychology which argued that the difference between the artist and the psychotic is that the artist can return from the world of his imagination to the real world, while the psychotic cannot. In 1938, Kris fled to England, after the psychotic artist Hitler invaded Austria. In exile he became a lecturer and training analyst at the London Institute of Psychoanalysis, and re-established his working relationship with Ernst Gombrich .For a time they both  analyzed Nazi radio broadcasts for the BBC. In 1940, Kris and his family moved to New York, where he became a visiting professor at the New School for Social Research, where he founded the Research Project on Totalitarian Communication (1941–44) 

A fellow student of Gombrich, was Otto Pächt (1902 –1988, ) who also  studied under von Schlosser.. Pächt was born in Vienna in 1902 into a Jewish family. His father David Pächt, a Jewish industrialist who owned a successful textile factory. He attended the 'Humanistisches Staatsgymnasium' in Vienna – a grammar school in which Latin and ancient Greek were taught as the basis of European culture. In 1920 entered university in Vienna to study art history ,except for one semester in Berlin studying with Adolph Goldschmidt. In Vienna  his dissertation on medieval painting in 1925 "Das Verhältnis von Bild und Vorwurf in der mittelalterlichen Entwicklung der Historiendarstellung", was supervised by von Schlosser.]Pächt became a key advocate of the so-called New Vienna School of Art History. Between 1926 and 1930 he co-edited the new serial "Kritische Berichte zur kunstgeschichtlichen Literatur" (founded by Pächt and Bruno Fürst in 1931 and 1933 edited the first (and only) two issues of "Kunstwissenschaftliche Forschungen" in collaboration with Sedlmayer). His doctoral dissertation (Habilitation) of 1932 was written on the painter Michael Pacher, supervised by August Grisebach at Heidelberg. It was published 1933 as a short article in the journal Kunstwissenschaftliche Forschungen. With the rise of National Socialism in Germany in 1933, Pächt's university post was revoked and he returned to Vienna. Shortly before the Anschluss, in 1938, Pächt left Austria to accept an invitation by the Irish George Furlong, Director of the National Gallery of Ireland. From 1937 until 1941, he lectured in London at the Courtauld Institute and Warburg Institute, whose director was the viennese Fritz Saxl. 

Friedrich "Fritz" Saxl (1890– 1948) studied in his native Vienna under Wickhoff, von Schlosser and Max Dvořák, who oversaw his dissertation on Rembrandt. He then moved to  Berlin and studied under Heinrich Wölfflin, and spent 1912–13 researching in Italy for his only major work, a study of medieval illuminated manuscripts with astrological and mythological elements- . He served in the Austro-Hungarian army as a lieutenant on the Italian front for the duration of World War I. Before the interruption of war service , in  1913 Saxl had joined what was then the Warburg Library at the Warburg Haus, Hamburg as librarian, and he returned in 1919, also lecturing at the University of Hamburg . On Warburg's death in 1929 Saxl formally became director, although he had effectively been in charge for several years already. With the Nazi regime in power, Saxl was instrumental in moving the Warburg Institute to safety in London in 1933, coming with it himself and settling in England, becoming a British citizen in 1940. His efforts at maintaining the Warburg Institute came at the cost of his own scholarly output, which was mostly restricted to papers and lectures. 

And so back to Thannhauser's professor Wilhelm Koehler. From 1903 to 1907 Koehler studied art history in Strasbourg, Bonn and Vienna. He received his doctorate in 1906 under Franz Wickhoff and Max Dvořák in Vienna and  from 1906 to 1909 he was assistant to Franz Wickhoff. From 1909 to 1914 he worked for the project Monuments of German Art of the German Association for Art History and began collecting material on Carolingian book illumination. In 1918 he became director of the newly founded State Art Collections in Weimar, where he made contact with the Bauhaus School. From 1920 he also taught art history at the University of Jena (1920 private lecturer, 1924 associate professor). In 1920 he married the Bauhaus student Margarete Bittkow. In 1932 Koehler first went to Harvard University as a visiting professor, then finally emigrated in 1934 and was appointed Professor of Medieval Art History as the successor to Arthur Kingsley Porter. He taught at Harvard until his retirement in 1953. From 1941 to 1944 he was the first senior research fellow at Dumbarton Oaks. From 1946, he was a corresponding member of the British Academy.The focus of his academic work was research on Carolingian book illumination, which he presented in the corpus volumes Die Carolingischen Miniatures. He began working on it immediately after completing his dissertation, the first volume being published in 1930 and the second in 1955. 

For a while there were actually two Vienna schools.  Josef Strzygowski, who was appointed in 1909, at the same time as Dvořák, was a vehement opponent of the traditional view of history, in place of which he advocated an anticlassical, antihumanist, and anticlerical outlook. In opposition to the standard view which was centred on ancient Greece and Rome, Strzygowski turned his attention towards the Orient, where he thought he had discovered the traces of an original "Nordic" character, which was superior to the "Mediterranean." He found himself in irreconcilable opposition to the "orthodox" branch of the Vienna School, in particular to the "arch-humanist" Schlosser, who on his side condemned Strzygowski as the "Attila of art history." The dispute resulted in a complete separation, not only ideological but also physical, so that two art-historical institutes existed within the university without any relationship to each other. Strzygowski devised a tabular method of "Planforschung," which was supposed to guarantee absolute objectivity, but in hindsight was completely impracticable and clearly intended to justify his abstruse theories. Strzygowski's worldview developed a markedly bizarre, racist tendency that approached Nazi ideology. However, his institute was closed upon his retirement in 1933. Nevertheless he opened up the consideration of non-European cultures and his esteem for abstract art, which he understood as uniquely "Nordic," was a step towards an art-historical confrontation with modernity. 

it was not just Vienna that was to be an fluence on future art history. Saxl also studied in Germany under Heinrich Wölfflin and Pächt with Adolph Goldschmidt  . Wölfflin (1864 –1945) was a Swiss art historian, aesthetician and educator, whose objective classifying principles ("painterly" vs. "linear" and the like) were influential in the development of formal analysis in art history in the early 20th century.[1] He taught at Basel, Berlin and Munich in the generation that saw German art history's rise to pre-eminence. His three most important books, still consulted, are Renaissance und Barock (1888), Die Klassische Kunst (1898, "Classic Art"), and Kunstgeschichtliche Grundbegriffe (1915, "Principles of Art History").Wölfflin taught at Berlin University, from 1901 to 1912, at Munich University, from 1912 to 1924, and at Zurich University, from 1924 until his retirement.Wölfflin was following in the footsteps of Vasari, among others, in devising a method for distinguishing the development in style over time. He applied this method to Trecento, Quattrocento and Cinquecento art in Classic Art (1899), then developed it further in The Principles of Art History (1915). Wolfflin's Principles of Art History has recently become more influential among art historians and philosophers of art. 

Adolph Goldschmidt (1863 – 1944) was born in the Free and Hanseatic City of Hamburg.[1] His family was Jewish and in the banking business.[1] After a short business career he devoted himself (1885) to the study of the history of art at the universities of Jena, Kiel, and Leipzig. He took his degree in 1889 with the dissertation, Lübecker Malerei und Plastik bis 1530 (Lübeck painting and sculpture until 1530), the first detailed analysis of the medieval art of northeast Germany. After traveling through Germany, Denmark, Sweden, the Netherlands, England, France, and Italy, he became Privatdozent at the University of Berlin. Notable students of Goldschmidt include Klara Steinweg. His work, Studien zur Geschichte der Sächsischen Skulptur in der Uebergangszeit vom Romanischen zum Gotischen Stil (English: Studies on the history of Saxon sculpture in the transition period from the Romanesque to the Gothic style) (Berlin, 1902) traces the gradual development of German sculpture with reference to the period of its florescence in the thirteenth century. His work, Die Kirchenthür des Heil. Ambrosius in Mailand (English: The church door of salvation. Ambrose in Milan) (1902) for the first time showed the door of the Basilica of Sant'Ambrogio in Milan to be a monument of early Christian art. He also contributed a number of important articles on North-German painting, Saxon sculpture, and early medieval miniature manuscripts to the Repertorium für Kunstwissenschaft, Zeitschrift für Christliche Kunst, and Jahrbuch der Kgl. Preussischen Kunstsammlungen. Being of Jewish origin, he had to flee Nazi Germany. He died in Basel, Switzerland on 5 January 1944, aged 80. 

Erwin Panofsky was born in Hannover to a wealthy Jewish Silesian mining family. He grew up in Berlin, receiving his Abitur in 1910 at the Joachimsthalsches Gymnasium. In 1910–14 he studied law, philosophy, philology, and art history in Freiburg, Munich, and Berlin, where he heard lectures by the art historian Margarete Bieber, who was filling in for Georg Loeschcke. While Panofsky was taking courses at Freiburg University, a slightly older student, Kurt Badt, took him to hear a lecture by the founder of the art history department, Wilhelm Vöge, under whom he wrote his dissertation in 1914. His topic, Dürer's artistic theory Dürers Kunsttheorie: vornehmlich in ihrem Verhaltnis zur Kunsttheorie der Italiener was published the following year in Berlin as Die Theoretische Kunstlehre Albrecht Dürers. Because of a horse-riding accident, Panofsky was exempted from military service during World War I, using the time to attend the seminars of the medievalist Adolph Goldschmidt in Berlin. The original 1920 manuscript of Panofsky's Habilitationsschrift, his second dissertation, which is titled "Die Gestaltungsprinzipien Michelangelos, besonders in ihrem Verhältnis zu denen Raffaels" ("The Composition Principles of Michelangelo, particularly in their relation to those of Raphael"), was found in August 2012 by art historian Stephan Klingen in an old Nazi safe in Munich's Zentralinstitut für Kunstgeschichte. Panofsky's academic career in art history took him to the University of Berlin, University of Munich, and finally to University of Hamburg, where he taught from 1920 to 1933. It was during this period that his first major writings on art history began to appear. A significant early work was Idea: Ein Beitrag zur Begriffsgeschichte der älteren Kunstheorie (1924; translated into English as Idea: A Concept in Art Theory), based on the ideas of Ernst Cassirer. Panofsky first came to the United States in 1931 to teach at New York University. Although initially allowed to spend alternate terms in Hamburg and New York City, after the Nazis came to power in Germany his appointment in Hamburg was terminated because he was Jewish, and he remained permanently in the United States with his art historian wife (since 1916), Dorothea "Dora" Mosse (1885–1965). By 1934 he was teaching concurrently at New York University and Princeton University, and in 1935 he was invited to join the faculty of the new Institute for Advanced Study in Princeton, where he remained for the rest of his career. While Panofsky as at Hamburg , his first student was Edgar Wind 

Wind was born in Berlin, son of Maurice Delmar Wind, an Argentinian merchant of Russian Jewish ancestry, and his Romanian wife Laura Szilard. He received a thorough training in mathematics and philosophical studies, both at the Gymnasium in Charlottenburg, and then at university in Berlin, Freiburg, and Vienna. He completed his dissertation in Hamburg under Panofsky. Wind left to teach briefly in the United States for financial reasons (he had a two-year appointment at the University of North Carolina from 1925 to 1927), but then returned to Hamburg as a research assistant. It was there that he got to know Aby Warburg, and was instrumental in moving the Warburg Library out of Germany to London during the Nazi period. Warburg's influence on Wind's own methods was significant. Once in London, Wind taught and became involved with the Warburg Institute, helping found the Journal of the Warburg and Courtauld Institute in 1937. During the war he returned to the US and remained there, holding several teaching positions, at New York University, University of Chicago, and Smith College.. He is best remembered for his research in allegory and the use of pagan mythology during the 15th and 16th centuries, and for his book on the subject, Pagan Mysteries in the Renaissance.well as the first Professor of art history at Oxford University.  

Panofsky's early work drew on the ideas of German philosopher Ernst Alfred Cassirer ( 1874 –1945). Trained within the Neo-Kantian Marburg School, he initially followed his mentor Hermann Cohen in attempting to supply an idealistic philosophy of science. At Hamburg Cassirer discovered the Library of the Cultural Sciences founded by Aby Warburg. Warburg was an art historian who was particularly interested in ritual and myth as sources of surviving forms of emotional expression. In Philosophy of Symbolic Forms (1923–29) Cassirer argues that is a "symbolic animal". Whereas animals perceive their world by instincts and direct sensory perception, humans create a universe of symbolic meanings. Cassirer is particularly interested in natural language and myth. He argues that science and mathematics developed from natural language, and religion and art from myth. Politically, Cassirer supported the liberal German Democratic Party (DDP). After working for many years as a Privatdozent at the Friedrich Wilhelm University in Berlin, Cassirer was elected in 1919 to the philosophy chair at the newly founded University of Hamburg, where he lectured until 1933, supervising amongst others the doctoral theses of Joachim Ritter and Leo Strauss.. Cassirer left Germany on 12 March 1933 - because he was Jewish. After leaving Germany he taught for a couple of years at the University of Oxford, before becoming a professor at Gothenburg University. In 1941 he became a visiting professor at Yale University, then moved to Columbia University in New York City, where he lectured from 1943 until his death in 1945. 

Another former pupil of Wölfflin was Jakob Rosenberg (1893 –1980) an art historian, museum curator, and educator noted particularly for published work on Rembrandt. Rosenberg was born in Berlin into a family of art dealers. His brother Saemy Rosenberg (1893–1971) continued the business in Germany, the Netherlands, and the United States. During the years 1912 to 1914 he first did an internship in the art trade in Munich. After serving in a cavalry unit in World War I he was wounded, captured by the British and sent to Scotland. In 1915 and was sent to Switzerland by prisoner exchange. After the war he studied art history in Bern and Zurich, then in Frankfurt and Munich, where he received his doctorate under Heinrich Wölfflin. He then worked for Max J. Friedlander in the Berlin print cabinet Kupferstichkabinett Berlin, where he also had contact with Wilhelm von Bode. In 1932, Friedländer and Rosenberg published their book on the paintings of Lucas Cranach the Elder (Die Gemälde von Lucas Cranach der Äe). In 1935 he became a curator at the Kupferstickkabinett. Rosenberg was of Jewish descent, and resigned from his position in the same year. His colleague Friedländer had retired in 1933 for similar reasons. Their work on Lucas Cranach was interrupted, and their second book on Cranach's drawings was only published in 1960, two years after Friedländer's death in the Netherlands. After a visit to Harvard University in 1936, Jakob Rosenberg emigrated to the United States in 1937 and became a research fellow and at Harvard on the recommendations from Adolph Goldschmidt and his friend Paul Sachs. In 1940 he was appointed as an associate professor and in 1947 as a full professor. His 1948 overview work on Rembrandt was reprinted in 1964 and 1968, holding its own as a standard work during the early years of the Rembrandt Research Project. He was also director of the Graphic Collection of the Museum of Fine Arts, Boston from 1939, and was appointed as Curator of Prints at the Fogg Museum in 1949. 

Frederick Antal ( 1887 – 1954), ( Frigyes Antal), was born in Budapest to an upper-class Jewish family. After earning a degree in law, he decided to pursue art history. He studied with Heinrich Wölfflin at the University of Berlin before completing his doctorate under Max Dvorák .He started his career at the Museum of Fine Arts in Budapest with a year as a volunteer during the war. In 1919, he became its Vorsitzender des Direktoriums (Chairman of the Board) for several months until the White Terror toppled the new Hungarian Soviet Republic and he fled the country. After a brief sojourn in Vienna, Antal lived in Germany . From 1926 to 1934, he was an editor for Kritische Berichte zur kunstgeschichtlichen Literatur, alongside Bruno Fürst. In 1933, he was forced to flee from political upheaval again, as the Nazi Party rose to prominence in Germany. Settling in England, he lectured at the Courtauld Institute of Art in London becoming a leading practitioner of the social history of art in Britain. Antal applied a Marxist dialectical materialism to art history", suggesting that "artistic style is primarily an expression of ideology, political beliefs and social class". 

Paul Frankl (1878 – 1962) was born in Prague into the prominent rabbinic Spira-Frankl family. From 1888 to 1896, he attended a German Gymnasium, after which he enrolled in the German Staats-Obergymnasium of Prague, graduating in 1896. He served for one year as Lieutenant in the Austrian military. In order to pursue a degree in higher education, he converted to Catholicism, a move that was not uncommon among non-Catholics during this era. He matriculated to the Technische Hochschule in Munich and, later, Berlin, and graduated with a degree in architecture in 1904. While in Berlin, Frankl fostered social relationships within circles of philosophers and artists whose members who introduced him to new systems of thinking, such as Gestalt psychology. In 1908, Frankl left his work as an architect to study philosophy, history, and art history at the Ludwig-Maximilians-Universität in Munich under Heinrich Wölfflin and Berthold Riehl, the founder of the Institut für Kunstgeschichte. Riehl supervised Frankl's doctoral dissertation on fifteenth-century glass painting in southern Germany. After the completion of his dissertation in 1910, Frankl worked as Wölfflin's assistant and wrote his Habilitationsschrift, which offered a systematic definition of the formal principles of architecture from the Renaissance onwards. From 1914 to 1920, Frankl held a position as privatdozent, which enabled him to teach at the University of Munich while contributing to the Handbuch der Kunstwissenschaft . In 1914, Frankl wrote his first theoretical work, Die Entwicklungsphasen der neueren Baukunst in which he proposed four major categories of art history analysis - spatial composition, treatment of mass and surface, treatment of optical effects, and the relation of design to social function.  Frankl held an assistant professorship at the Ludwig Maximilian University of Munich from 1920 to 1921, after which he became full professor at Halle University. It was here that Frankl initiated his lifelong interest in medieval architecture. His study, Die frühmittelalterliche und romanische Baukunst (1926) exemplified distinctions between Romanesque and Gothic architecture - the former being "additive", "frontal", and "structural" while the latter is "partial", "diagonal", and "textural". The Nazis terminated Frankl's position in Halle in 1934. Upon leaving the university, Frankl returned to Munich and wrote his monumental treatise, Das System der Kunstwissenschaft (1938), which offered a comprehensive history of art grounded in phenomenology and morphology. Das System was issued in Czechoslovakia since Jewish authors were censored in Germany and Austria. He  travelled to the United States in 1938, where he sought work and refuge from the Nazis. Although he was fluent in seven languages, English was not his strength. After six months, Frankl's visa expired and he became desperately ill. In order to apply for US citizenship, he sailed to Cuba – so as to step on "foreign" soil – and re-entered the United States as an immigrant. In 1939, with the assistance of Max Wertheimer, Paul Oskar Kristeller, and Erwin Panofsky, Frankl received a position as art historian at the Institute of Advanced Study at Princeton University. 

Richard Krautheimer (1897 – 1994 ) was the son of Nathan Krautheimer and Martha Landmann). He fought in the First World War as an enlisted soldier in the German army . Between 1919 and 1923, he initially studied law at, successively, universities in Munich, Berlin, and Marburg under faculty who included Heinrich Wölfflin, Adolf Goldschmidt and Werner Weisbach. During these years, he briefly worked on the state inventory of Churches for Erfurt (Inventarisierung der Erfurter Kirchen für die Preussische Denkmalpflege). He completed his dissertation in Halle under Paul Frankl in 1925 with the title Die Kirchen der Bettelorden in Deutschland (1240–1340). Frankl's work remained a strong influence for Krautheimer and his systematizing methodology. In 1927 he completed his Habilitation under Richard Hamann in Marburg. The same year, while researching at the Bibliotheca Hertziana in Rome, Krautheimer developed the idea for a handbook of Roman churches with a colleague, Rudolf Wittkower, later to become the Corpus Basilicarum. In 1928 he accepted a privatdozent teaching position at Marburg. Except for studies-in-residence at the Hertziana he remained at Marburg. The Krautheimers fled Nazi persecution, leaving Germany for good. Between 1933 and 1935 Krautheimer worked on the Corpus, accepting paying employment from Frankl's son in the city. The declining situation for Jews in Germany compelled  Krautheimers to emigrate to the United States, where he found a position at the University of Louisville, Kentucky, At his request, Louisville hired another fleeing art historian, Krautheimer's friend from school days, Justus Bier. Krautheimer moved to Vassar in 1937 at the request of Vassar's Art Department chair, Agnes Claflin. That same year saw Krautheimer's first volume of the Corpus Basilicarum Christianarum Romae, a scholarly inventory and documentation of the early Christian churches in Rome eventually running to five volumes. The set would not be completed until 1977. Following US entry into World War II, he became a naturalized citizens and volunteered for duty as a senior research analyst for the Office of Strategic Services where he analyzed aerial photographs of Rome to assist in the protection of historic buildings during bombing. While still at Vassar, he taught  at New York University (1938–49).  He moved to NYU permanently in 1952 as the Jayne Wrightsman Professor of Fine Arts. 

Justus Bier (1899 – 1990)  grew up in a wealthy Nuremberg family where he attended the Humanistisches Gymnasium in that city. After graduation in 1917, he fought in the first World War. Between 1919 and 1924 he studied art history, archaeology, and medieval and modern history at the universities in Munich, Erlangen, Jena, Bonn and finally Zürich. His major professors were Paul Clemen and Heinrich Wölfflin. His dissertation, written under Wölfflin, was on the early work of his home town’s most famous artist, Tilman Riemenschneider. It was granted in 1924 and published the following year. Between 1924-1930 Bier he began publishing his magisterial book on Riemenschneider while lecturing (Dozent) at the Volkschule. He also contributed articles on modern architecture. In 1931 he married the art historian Senta Dietzel (1900-1978), whose brother was the gallery owner Max Dietzel. From 1930-36 Bier was a curator of the Kestner Society and Museum in Hannover which mounted contemporary art exhibitions. Bier himself collected the work of Bauhaus artists Paul Klee, Oskar Schlemmer and Lyonel Feininger. In 1936 the Nazi government closed the Kestner Society and banished Bier, who was Jewish. In 1937 he emigrated to the United States. His former classmate, Richard Krautheimer recommended Bier for the position he was vacating at the University of Louisville, Bier taught art history there 1937-60, acting as Chair of the department 1946-60. Werner Weisbach ( 1873 –  1953, ) was a German-Swiss historian. He studied art history, archaeology, history and philosophy at the universities of Freiburg, Berlin, Munich and Leipzig, receiving his promotion from the latter institution in 1896 (Following a study trip through Europe, he served as a volunteer at the Museum of Berlin under the directorship of Wilhelm von Bode. From 1903 onward, he worked as a lecturer at Friedrich-Wilhelms-Universität in Berlin, where from 1921 to 1933 he taught classes as an associate professor of art history. During the era of National Socialism he emigrated to Basel, Switzerland as a private scholar (1935). 

Paul Oskar Kristeller (1905–1999 ) received a PhD from the University of Heidelberg in 1928.under Ernst Hoffmann with a dissertation on Plotinus. He did postdoctoral work at the universities of Berlin and Freiburg. At Freiburg, Kristeller studied under the philosopher Martin Heidegger from 1931 to 1933. The Nazi victory in 1933 forced Kristeller to move to Italy. At his arrival, the Fascist philosopher Giovanni Gentile secured for him a position as lecturer in German at the Scuola Normale Superiore in Pisa. It was at the Scuola Normale that Kristeller completed his first great works in the Renaissance: the Supplementum Ficinianum (1937) and The Philosophy of Marsilio Ficino (1943). In 1939, he fled Italy, due to the enactment of Mussolini's August 1938 racial laws, to live in the USA. Thanks to the help of Yale University historian Roland Bainton, he sailed from Genoa in February 1939 and by March was teaching a graduate seminar at Yale on Plotinus. However Kristeller taught for only a short time at Yale University until moving to Columbia University, where he taught until his retirement in 1973, as Frederick J. E. Woodbridge Professor of Philosophy.