Zamenhof Day Zamenhof Day Zamenhof Day (), also called Esperanto Book Day, is celebrated on 15 December, the birthday of Esperanto creator L. L. Zamenhof. It is the most widely celebrated day in Esperanto culture. On this day, Esperantists hold information sessions and cultural gatherings to promote literature in Esperanto. The history of celebrating Esperanto on Zamenhof's birthday can be traced back to 17 December 1878, when at a birthday party for his 19th birthday he presented to his friends his "Lingwe uniwersala", the first version of his international language. By 1887, this language had evolved into what is now recognized as
Justus Ludwik Decjusz Justus Ludwik Decjusz Justus Ludwik Decjusz (, ; 1485–1545) was a notable Polish burgher and diplomat of German origin in 16th-century Kraków. He served as a finance minister and secretary to the Polish king Sigismund I the Old. Originally from Alsace, Decjusz's career peaked with his appointment as the king's personal adviser and overseer of the royal mint. He was also the author of a widely circulated text "De vetustatibus Polonorum" (, "On the Ancient Origins of the Poles"), an early version of the Sarmatian myth about the origin of the Polish kings. He also wrote "Księga o czasach króla