Hi Kay, I ran across this article at the Walker County Genweb site:
"Manasco, Jeremiah, a native of Wales, who came to Virginia during Colonial times, was a Captain in the Revolutionary Army, subsequently lived in North and South Carolina and in Alabama, and has many descendantes in Walker County, Alabama-Dombhart's History of Walker County, Alabama, pp. 276"
Also Manasco's listed in the 1840 Walker Co., Alabama Tax Lists were:
Beat 1:John Manasco Beat 4:Willis Manasco Beat 15: David Manasco Beat 15: W. B. Manasco
Hope this helps you in some way. I am not researching this Manasco line. Jan