Painter, etcher, and graphic designer Johanna (Tanna) Kasimir-Hoernes was born Joanna Hoernes on January 31, 1887, in Graz, Austria. Her mother was poet and writer Jenny Hoerne (née von Reuss) and her father was geologist Rudolf Hoernes. Her formal art training began in 1905 at the School for Women and Girls with Ludwig Michalek, followed by the Vienna Academy of Art beginning in 1909 with Wilhelm Unger. During the summers she studied at the workshop of artist Adolf Holzel in Dachau.

It was at the Academy that she met her future husband, artist Luigi Kasimir, and participated in her first exhibion in 1910. Her second exhibition took place the same year with the Association of Fine Arts of Styria, winning a silver medal for her etching "Bridge Workers". She and Luigi married in 1911, and began working collaboratively to develop an innovative, painterly color etching technique that contributed to the Etching Revival of the late 19^th and early 20^th century.

During the First World War she was commissioned to travel to Belgium, Galicia, and Northern Italy to record the conflicts in drawings, which would then become a portfolio of twelve lithographs, titled Podolian, published by Hugo Heller in 1917. Before and after the war she and Luigi traveled extensively throughout Europe and United States, and the two produced extensive "city veduta" works that focused on major architectural and natural landmarks. As well, Kasimir-Hoernes illustrated several books and periodicals, including Herman von Hoernes' Book of Flight (1911); Margarethe von Schuch-Mankiewicz' Platz der Jugend (1912); and the magazines The Studio (London, 1911), Donauland (Austria, 1917), and Moderne Welt (Austria, 1924), among others.

Though frequently overshadowed by her husband in the annals of art history, Kasimir-Hoernes was herself a prolific artist, creating a large body of work that reflected her and Luigi’s extensive worldwide travels. During the Association of Women Artists of Vienna Exhibition of 1916, critic Albert Seligmann judged her work to be superior to that of her more well-known husband's, stating that it was "actually more snappy and daring in its treatment...although the model cannot be mistaken." (Neue Frei Presse, Feb. 22, 1916, p. 11).

Tanna and Luigi lived in Vienna for the entirety of their lives, and had a son, Robert, who himself became a noted artist. Tanna died in Vienna on June 16, 1972.

Awards:
1910: silver medal, City of Graz, Association of Fine Artists of Styria
1914: honorary award, Bugra Exhibition, Leipzig
1915: bronze medal in etching, Pan-Pacific Int'l Expo., San Francisco, CA

Selected Exhibitions: 
1906: Vienna Etching Club 4th Annual Exhibition
1910: Vienna Academy of Art (annual exhib.); Association of Fine Artists of Styria, silver medal (awarded by City of Graz)
1911: Radierclub Wiener Kunsterinnen (art group)
1912: Association of Women Artists of Austria, annual exhibition
1914: Bugra 1914 Exposition, Leipzig
1915: Pan-Pac. Int'l Expo, San Francisco, CA
1917: War Graphics Exhibition, Leipzeig and Vienna
1919: Vienna Secession exhibition
1919 and beyond: Association of Women Artists in Austria
1921: exhibition with Luigi Kasimir, Hellersche Bookstore, Vienna
1931: exhibition with Luigi Kasimir, Halm & Goldman Art Gallery, Vienna
1934: Austrian War Pictures, 1914-1918 (group exhibition), Vienna Kunstlerhaus
2020: Ladies First! Female Artists In and From Styria, 1850 - 1950, Neue Galerie Graz (posthumous)