I stand by a statue of St Louis IX at Sacré-Cœur basilica in Paris. He was the King that led the 7th crusade against the Muslims, mainly in Egypt.
During the end of the campaign, Egypt Sultan Salih Ayub died, and his widow Shajar AdDur took lead of the nation, streghtened the army under Mamluk command with heroes like Qutuz & Baibars (the ones who will be the first to defeat the mighty Mongol army at Spring of Goliath). This Muslim army defeated the crusaders at the final battle at Fariskur, captured King Louis, and ended the the 7th crusade campaign. King Louis was ransomed at a high price equivalent to a year of France’s annual revenue. It was reported that it took 2 days to count the gold.