L. L. Zamenhof | Ludwik Solski Academy for the Dramatic Arts | Ludwik Starski | Ludwik Rajchman | Ludwik Mlokosiewicz | Ludwik Konarzewski-junior | Ludwik Hieronim Morstin | Adam Ludwik Czartoryski |
The most prosperous were Volapük (1879, Johann Martin Schleyer), Esperanto (1887 Ludwik Lejzer Zamenhof), Latino sine flexione (1903, Giuseppe Peano), Ido (1907, Louis Couturat), Occidental-Interlingue (1922, Edgar de Wahl) and Interlingua (1951, IALA and Alexander Gode), with Esperanto being the only one still gathering a considerable community of active speakers today.