Louis I of Blois
Louis I of Blois (1172–1205), son of Theobald V and Alix of France, was count from 1191 and fought on the Third Crusade. He married Catherine of Clermont, bearing his heir Theobald VI; in 1196 he freed his serfs.
At Écry on 28 November 1199 he and his cousin Theobald III became the first nobles to take the cross for the Fourth Crusade. He commanded a division at Constantinople in 1203, but fever kept him from its 1204 sack. Pursuing Kaloyan's Cumans too far at Adrianople, he was killed on 14 April 1205.