Jan Lorentowicz (14 March 1868 – 15 January 1940; occasional pen name, M. Chropieński) was a Polish theatre director, literary critic, publicist, editor and book collector; president of the Polish PEN Club (1925–27); and from 1938, an elected member of the prestigious Polish Academy of Literature. In 1919, in celebration of Poland's return to independence (1918) after over a century of partitions, Lorentowicz published the most complete collected works of the poet Jan Kochanowski (1530–1584), who had laid the foundations for Polish literary language.