Although he was British, I decided to focus on Tarleton because Jason Isaac's character Col. William Tavington of "The Patriot" was based on Banastre Tarleton.
Banastre Tarleton was born in Liverpool on August 21, 1754 to a wealthy family. His father died when Tarleton was nineteen, leaving him with an inheritance that he quickly squandered. Penniless (actually, he was in debt), he convinced his mother to purchase him a rank in the cavalry. In 1776, he volunteered to ship out to the Colonies, where he was stationed in New York. Along with New York and Pennsylvania Loyalists, he worked in the Green Dragoons -- their coats were mostly green, not red, as is depicted in "The Patriot" -- and became known as "Bloody Ban" or "The Butcher" following the Waxhaw Massacre.
His ruthless effectiveness earned him a promotion to Major under Gen. Lord Cornwallis, and he was transferred to Col. William Harcourt. On Dec. 13, 1776 Tarleton captured Colonial Gen. Charles Lee, and in 1780 he moved south and captured Charles Towne, SC. On May 29 of the same year, Tarleton butchered 113 of 350 Virginia Continentals at the Battle of Waxhaw. Although 203 were captured, only 53 were able to travel with them -- the rest were left behind. Reports conflict as to whether Tarleton's men began the massacre under his orders or because his horse was shot and pinned him to the ground, leading his men avenge him because they thought he'd been shot under truce. Thereafter, the Patriots were known to refer to "no quarter" as "Tarleton's Quarter."
As is portrayed in "The Patriot," Tarleton did hunt for Francis Marion (Mel Gibon's character Benjamin Martin), and gave Marion the nickname "Swamp Fox."
Following the defeat of the British at Cowpens and then Yorktown, Tarleton returned to England (he wasn't bayoneted through the throat by a vengeful Francis Marion) and held political office in Parliament.