Historian of Italian renaissance; collaborator with Richard Offner on the Critical and Historical Corpus of Florentine Painting. Steinweg studied at various German universities as was common for scholars at that time, beginning in 1922 attending classes under Heinrich Wölfflin in Munich, Adolph Goldschmidt in Berlin, and by 1925 settling at Göttingen where she wrote her dissertation under Georg Vitzthum von Eckstädt. Her dissertation topic, on Andrea Orcagna, was published in 1929. Steinweg met New York University scholar Richard Offner during this time. After her degree, she became a volunteer assistant at the Dresden Gallery where her initial interest was in 18th-century Venetian art. She wrote the catalog for the "modern" collection in Dresden and contributed the articles on G. A. Pellegrini and D. Zanetti for the Allgemeine Künstlerlexikon (Thieme-Becker). In 1930 Offner offered her a position as his assistant in Europe on his forthcoming corpus of Florentine Painting, the Critical and Historical Corpus of Florentine Painting. Steinweg agreed, moving to Berlin. Already the first four volumes of the Corpus were in production and, although she made alterations to these volumes, her work began in earnest with volume five. In Berlin, Steinweg was responsible for the discovery of many fourteenth-century paintings in German private collections. In 1935 she moved to Florence to work on the project there with Offner at the project's headquarters in Offner's Tuscan home. The same year Werner Cohn joined the Corpus. When World War II was declared, Steinweg returned to Germany, where she remained until the surrender. For the next twenty years she worked almost exclusively on the project until Offner's death in 1965. The project was then moved to the Kunsthistorisches Institut in Florence and Steinweg appointed official co-author, carrying on the work alone at the request of the Institute of Fine Arts. This entailed filing pictures and her research in the various files of the Corpus for publication at some date. Such a procedure forced her to watch as other scholars published pictures long known to her with similar findings. She published little outside the Corpus in her lifetime, largely material that was outside the parameters of the project. The Corpus has continued under Miklós Boskovits and Mina Gregori. After her death, two numbers of the Mitteilungen des Kunsthistorischen Institutes in Florenz were published as a festschrift in her memory in 1973. Steinweg was a conventional art historian for her era: her interest, bordering on devotion, was to the work itself and the history of artists and their immediate situation (Hueck). She focused on the historical documents and stylistic criticism for her method (Quellengeschichte and stilkritische Untersuchungen).
[complete bibliography:] "Bibliographie von Klara Steinweg." Mitteilungen des Kunsthistorischen Institutes in Florenz 17 no.2-3 (1973): 371-372; [dissertation:] Andrea Orcagna: quellengeschichtliche und stilkritische Untersuchung. Göttingen, 1929, published, Strassburg: J. H. E. Heitz, 1929; Katalog der modernen Galerie [of the] Staatliche Gemäldegalerie zu Dresden. Dresden: W. und B. v. Baensch Stiftung, 1930; A Critical and Historical Corpus of Florentine Painting. New York: Institute of Fine Arts, New York University, 1930-1972.
Ladis, Andrew. "The Unmaking of a Connoisseur." in, Offner, Richard. A Discerning Eye: Essays on Early Italian Painting. University Park, PA: Pennsylvania State University Press, 1998, p.17; [obituary:] Hueck, Irene. "Klara Steinweg." Burlington Magazine 115, No. 843 (June 1973): 397.