[1] While in Berlin, Frankl fostered social relationships within circles of philosophers and artists whose members included fellow Pragueian Max Wertheimer, who knew Käthe Kollwitz.

[1] 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 (ed.

His study, Die frühmittelalterliche und romanische Baukunst (1926) exemplifies his categorical distinctions between Romanesque and Gothic architecture - the former being "additive", "frontal", and "structural" while the latter is "partial", "diagonal", and "textural".

[2] In 1933, Frankl's enthusiasm for medieval architecture led him to join a group of medievalists at the 13th International Congress of the History of Art in Stockholm to view the only gothic church whose original wooden arch scaffolding was still extant.

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.

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.

Wolfgang had left Germany in 1933 to live in Rome, but the increased Fascist threat prompted him to seek safety in England.

As a personal response to the plight of the Jewish people and his family, Frankl joined a committee at Princeton that sought to hypothesize a world government system that would ensure that racial genocide could never happen again.

These works revealed Wölfflin's continued influence on Frankl, who applied his former advisor's ideas of architectural style while supplementing his study with an analysis of social function and religious significance.

[1] Materials relating to Frankl's life and work are currently held at the Leo Baeck Institute in NY, USA, and the Exil Literatur Archive in Frankfurt, Germany.