Next year Matejko received a Doctor of Philosophy degree, "honoris causa", from the Jagiellonian University, and the Austrian "Litteris et Artibus". In 1888 he finished "Battle of Racławice" ("Bitwa pod Racławicami"). In 1888-1899, to justify his new academic title, he published a cycle of twelve sketches with an accompanying commentary, "History of civilization in Poland" ("Dzieje Cywilizacji w Polsce"). From 1890 to 1892, he published another cycle of sketches, this time of Polish kings ("Poczet królów i książąt polskich" - "Fellowship of the kings and princes of Poland"), which over the years became so popular that its portraits are seen as the canon portrayals of their subjects. 1891 saw him finishing "Constitution of the 3 May" ("Konstytucja 3 Maja"). He then began composing another large painting, "Oaths of Jan Kazimierz" ("Śluby Jana Kazimierza"), but it remained unfinished due to his death. In 1892, a year before his death, he finished a "Self-portrait" ("Autoportret").