Not much is known about the history of Tillie the Hun. One can only speculate how she came about her moose-like might. Speculations into her true nature include, but are not limited to...
She was born a mutant (Ah yes, the classic copout).
She is an Earthbound Asgardian (Hmmm. Maybe).
She is the product of Nazi experimentation (Quite possibly).
While on a high school field trip, she was bitten by a radioactive ox (Not likely, but the mere visual has me rooting for this one).
...Whatever her origins, she has exhibited the physical capability of confronting the likes of the Hulk and the She-Hulk. She appears to be a fierce combatant, knowledgeable in the use her spiked mace.
Like all other members of "The Band of the Bland", she was a remarkable failure as a super-villain. Joining Doctor Angst in his campaigns to assassinate Presidential candidate Howard the Duck and enact "The Cosmic Squish", she continues to be a failure as a super-villain to this very day.
Tillie the Hun was created by Steve Gerber
and Sal Buscema
in 1976 and first appeared in Marvel Treasury Edition