Where did Hobbits come from?

[William Cloud Hicklin]

Really. There's linguistic evidence in the texts that at some point they shared land with the ancestors of the Rohirrim - this could indeed have been a common ancestor from which descended both the contemporary Hobbits and Rohirrim.

Ahh, but Tolkien explicitly tells us that Hobbits, if they ever had a language of their own, had long forgotten it, picking up instead the languages of the Big Folk near whom they dwelt. It makes perfect sense that the Hobbits living in the vicinity of Greenwood/Mirkwood would have spoken or been influenced by the tongue of the Men of Rhovanion, ancestors of the Rohirrim.