My father's line, which admittedly has one weak link in the chain, (illegitimacy in 1776) has been traced back by another researcher to c1300. The family was not grand, just tenant farmers who rented their land from the same family for over 400 years! The manorial records just happen to have survived. On his maternal side, I have two lines which go back confirmed to 1540 approx, no known weak links. On my mother's side one line goes back into the early 16th century. A researcher, now sadly deceased at Doncaster traced his tree back to a Saxon nobleman known as Thorkell.
Much depends on the survival of records, of course if you find aristocracy in any of your lines then the work may have already been done, but beware, there are many fake trees around from the 19th century!
