For what is Charles James Fox best remembered?

Charles James Fox (1749-1806) was a British politician
whose ideas were among the "most radical ever to be aired in Parliament of his era." He
was also the arch-rival of the popular Prime Minister William Pitt the Younger. Fox was
a conservative Whig and follower of Edmund Burke. Like Burke, Fox supported the American
cause during the colonies' revolt against England, and he was a vocal opponent of King
George III. He campaigned against slavery, advocated religious tolerance, and supported
the French Revolutionaries. Interestingly enough, Fox was close friends with King
George's son, the Prince of Wales. The King blamed Fox for many of the Prince's
"debauchery;" at one time considering abdication, the King refused to do so because he
knew Fox would rise to further power if his son became King. Later, when the
King fell into a fit of madness (probably from the hereditary disease, porphyria), he
mistakenly believed the hated Fox to be his friend, and his close ally, Pitt, his
enemy.