And like Braveheart, from a historical point of view is utter nonsense. I'll leave it to the excellent Paul Combs to deliver a suitably scathing reprimand in detail:

"It portrays the British during the Revolutionary War essentially as Nazis rather than with anything resembling historical accuracy. The British never burned women and children to death inside a church, and the evil British officer is more like Lucius Malfoy in the Harry Potter films than the historical figure he is supposedly based on, Colonel Tarleton (both roles were played by Jason Isaacs, ironically).

Paradoxically, Gibson’s heroic title character is based on Francis Marion, also known as the Swamp Fox. Historical records show that Marion was even more brutal towards Native Americans and his own slaves than the film’s British villain is purported to be. The Patriot is basically a propaganda film, and it rightly outraged British audiences."

Paul's full article (which discusses other historically inaccurate films too) is here, and is well worth a read.