Notes:

Although we don't know for certain what High Gothic actually is, the Ecclesiarchy and nobility of the Imperium probably don't communicate solely through angry chimpanzee noises.

This fact saddens me greatly.

For those who do not know, Esperanto is an artificial language that was designed to be a Lingua Franca for the whole planet.

It's been quite successful, because there are people who are actually native speakers of it. Not many though, only about 1000 or so, which isn't bad for something someone just made up.

Then again, when one of your main competitors is Klingon, it probably isn't a very hard niche to conquer.

More information on Esperanto can be found here.