L'Assassinat d'Henri IV

"In Paris, on May 14th 1610, at 2:15 p.m., king Henri IV is murdered by a fanatical catholic named Ravaillac."

King Henri IV of France was living out his final hours before being assassinated on 14 May 1610 in the streets of Paris. But who was this king, described as a "womaniser", and who wanted to take his life?