History of Esperanto

The constructed international auxiliary language Esperanto was developed in the 1870s and 80s by L. L. Zamenhof, and first published in 1887. The number of speakers has grown gradually over time, although it has not had much support from governments and international bodies, and has sometimes been outlawed or otherwise suppressed.

Around 1880, while in Moscow and approximately simultaneously with working on Esperanto, Zamenhof made an aborted attempt to standardize Yiddish, based on his native Bialystok (Northeastern) dialect, as a unifying language for the Jews of the Russian Empire. He even used a Latin alphabet, with the letters ć, h́, ś, ź (the same as in early drafts of Esperanto, later ĉ, ĥ, ŝ, ĵ) and ě for schwa. However, he concluded there was no future for such a project, and abandoned it, dedicating himself to Esperanto as a unifying language for all humankind.Paul Wexler proposed that Esperanto was not an arbitrary pastiche of major European languages but a Latinate relexification of Yiddish, a native language of its founder. This model is generally unsupported by mainstream linguists.

Zamenhof would later say that he had dreamed of a world language since he was a child. At first he considered a revival of Latin, but after learning it in school he decided it was too complicated to be a common means of international communication. When he learned English, he realised that verb conjugations were unnecessary, and that grammatical systems could be much simpler than he had expected. He still had the problem of memorising a large vocabulary, until he noticed two Russian signs labelled Швейцарская (švejtsarskaja, a porter's lodge – from швейцар švejtsar, a porter) and Кондитерская (konditerskaja, a confectioner's shop – from кондитер konditer, a confectioner). He then realised that a judicious use of affixes could greatly decrease the number of root words needed for communication. He chose to take his vocabulary from Romance and Germanic, the languages that were most widely taught in schools around the world and would therefore be recognisable to the largest number of people.

...
Wikipedia