Help identifying the parents of James Davis (~1783) of Frederick County, Virginia

I'm trying to break through a brick wall in my family tree and would appreciate some help. Growing up I always heard that our family was related to Jefferson Davis, the President of the Confederate State. I've read that an ancestor of mine, James Lucius Davis (1813-1871), was a cousin of his and I've also read that this was actually not true.

I'm looking for the parents of James Davis (father of James Lucius Davis), born about 1783, who was associated with Frederick County, Virginia.

What I know:

• James Davis, b. ~1783, Frederick County, VA
• Married Sally Jekyll Jones, b. ~1787 (I've taken her genealogy pretty far back)
• Their only known child was Col. James Lucius Davis
• James Lucius Davis was born January 25, 1813 in Clarke County, VA and died May 11, 1871

Any help would be greatly appreciated!