I always viewed Esperanto, a politically neutral artificial language created in 1887, as akin to Latin or Sanskrit — a good idea at the time, but no longer relevant to the modern world. Google obviously disagrees, having added Esperanto as the 64th supported language in Google Translate.
Esperanto was originally developed by L. L. Zamenhof as a means of uniting a growing international population under a common language denominator — an intellectual precursor to the internet, if you will. It is currently spoken by an estimated 10,000 to two million people throughout 115 countries, primarily in Europe, Eastern Asia and South America, though it has never been listed as an official secondary language of any recognised nation.
Google itself calls the addition a largely symbolic move, though its engineers were surprised by how well it integrated into the electronic system,
For Esperanto, the number of existing translations is comparatively small. German or Spanish, for example, have more than 100 times the data; other languages on which we focus our research efforts have similar amounts of data as Esperanto but don't achieve comparable quality yet.
Enjoy William Shatner beating the shit out of the Esperanto language in the 1956 feature film, Incubus above.