It is unknown what his history was before the start of the series.
Throughout The Vampire Diaries Series
In Somebody That I Used to Know, he and two other unknown vampires were feeding on people at a restaurant and Damon, Bonnie and Enzo walk in. They kill the two other vampires and Enzo comes after Lewis. He begins to stab him until it's revealed that Lewis is actually possessed by Beau. Damon comes over to the table and begins to extract his heart, but Bonnie stops him and tells him that Beau had helped Caroline and the twins, but Damon proceeds to rip his heart out, killing Lewis and Beau for the final time.
It is unknown what his actual personality was like as he was possessed by Beau at the time.
Lewis had short, black hair and dark, brown eyes. He wore fancy clothes, with a black suit and a light blue shirt with buttons underneath. The suit also had a pocket with a napkin placed in it.
- Somebody That I Used to Know (Death)
- Lewis is the English variation of the German and French Louis. It means "renowned warrior". 
- Since The Other Side is gone, and the existence of both peace and Hell is known, it is possible both Lewis and Beau went to one of these dimensions.