Walker was originally raised as an Englishman. He became a physician after he attended the College of William and Mary. He acquired a large portion of land and became a man of status when he married Mildred Meriwether. Thomas was a vestryman form 1744 to 1785, and then he served as a delegate of the House of Burgesses for Virginia. After he received a grant of 800,000 acres in what is now southeastern Kentucky, the Loyal Land Company selected to explore the region. During the journey, he documented many land features such as the Cumberland Gap. Walker also had a great effect in dealing with Indian affairs.

http://www2.vcdh.virginia.edu/lewisandclark/students/projects/adventurers/walkerbio.html