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, 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. When his elder brother, the emperor Baldwin I, was captured at the Battle of Adrianople in April 1205, Henry was chosen regent of the empire, succeeding to the throne when the news of Baldwin’s death arrived, He was crowned August 20, 1205.

Henry was a wise ruler, whose reign was largely passed in successful struggles with Kaloyan, Tsar of Bulgaria, and with his rival, Theodore I Lascaris, emperor of Nicaea. Henry appears to have been brave but not cruel, and tolerant but not weak; possessing "the superior courage to oppose, in a superstitious age, the pride and avarice of the clergy." The emperor died, poisoned, it is said, by his Greek wife, on June 11, 1216.