There are many orgins and meanings to this name. Tanya was derived from Tatiana. Which has meaning of saints name and also a Fairy Queen. Other names related to this is Tania and Tonya.
This is my name. I followed the history of the name to Titus an Etruscan king before Romulous -- this may or may not be true. Contrary to many name books Tanya DOES NOT mean fairy princess. Tatiana was the name of the fairy princess in Shakespeares "Midsummers Nights Dream," and I believe that this is where the impression that this name means fairy princess came from.