Henry (c. 1174-1216), was the second emperor of the Latin Empire of Constantinople. He was a younger son of Baldwin V, Count of Hainaut (later Baldwin VIII, count of Flanders), and Margaret I of Flanders, sister of Philip of Alsace, count of Flanders. Having joined the Fourth Crusade about 1201, he distinguished himself at the siege of Constantinople in 1204 and elsewhere, and soon became prominent among the princes of the new Latin Empire. Wikipedia
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