Dr. Ludovic Lazarus (Ludwik Lejzer) Zamenhof (December 15, 1859 - April 14, 1917) was a Polish-Jew ophthalmologist, philologist and the initiator of Esperanto, the most widely spoken constructed language to date. His native languages were Russian and Yiddish, but he also spoke Polish and German fluently. Later he learned French, Latin, Greek, Hebrew and English, and he also had an interest in Italian, Spanish and Lithuanian.
Zamenhof was born on December 15, 1859 in the town of Bialystok, in the part of Poland which was then a part of the Russian Empire, and the town's population was made up of three major ethnic groups: Poles, Belorusians, and a large group of Yiddish-speaking Jews. Zamenhof was saddened and frustrated by the many quarrels between these groups. He supposed that the main reason for the hate and prejudice lay in mutual misunderstanding, caused by the lack of one common language that would play the role of a neutral communication tool between people of different ethnic and linguistic backgrounds.
As a student at secondary school in Warsaw, Zamenhof made attempts to create some kind of international language with a grammar that was very rich, but also very complex. When he studied English (along with German, French, Latin and Greek), he decided that the international language must have relatively simple grammar with a wide use of suffixes to make new forms of the words.
By 1878, his project Lingwe uniwersala was almost finished. However Zamenhof was too young then to publish his work. Soon after graduation from school he began to study medicine, first in Moscow, and later in Warsaw. In 1885, Zamenhof graduated from university and began his practice as an ophthalmologist. While healing people he continued to work on his project of the international language.
For two years he tried to raise funds to publish a booklet describing the language until he received the financial help from his future wife's father. In 1887, the book titled as "Lingvo internacia. Antaŭparolo kaj plena lernolibro" (International Language. Foreword And Complete Textbook) was published under the pseudonym "Doktoro Esperanto" (Doctor Hopeful), from which the name of the language derives. For Zamenhof this language wasn't merely a communication tool, but a means of spreading his ideas on the peaceful coexistence of different peoples and cultures.