L. L. Zamenhof L. L. Zamenhof Ludwik Lejzer Zamenhof (; , ; – ), credited as L. L. Zamenhof and sometimes as the pseudonymous Dr. Esperanto, was a Polish-Jewish ophthalmologist and the creator of Esperanto, the most successful constructed language in the world. He grew up fascinated by the idea of a world without war and believed that this could happen with the help of a new international auxiliary language, which he first developed in 1873 while still in school. Zamenhof was born on 15 December (3 December OS) 1859, the son of Markus Zamenhof (27 January 1837 - 29 November 1907) and
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