The Count of Hainaut (French: Comte de Hainaut; Dutch: Graaf van Henegouwen; German: Graf von Hennegau) was the ruler of the county of Hainaut, a historical region in the Low Countries (including the modern countries of Belgium, the Netherlands, Luxembourg and parts of northern France and western Germany). In English-language historical sources, the title is often given the older spelling Hainault.
John III the Pitiless (1374 – 6 January 1425), of the House of Wittelsbach, was first bishop of Liège 1389–1418 and then duke of Bavaria-Straubing and count of Holland and Hainaut 1418–1425.
Baldwin I (Dutch: Boudewijn; French: Baudouin; July 1172 – c. 1205) was the first Emperor of the Latin Empire of Constantinople; Count of Flanders (as Baldwin IX) from 1194 to 1205 and Count of Hainaut (as Baldwin VI) from 1195 to 1205. Baldwin was one of the most prominent leaders of the Fourth Crusade, which resulted in the sack of Constantinople in 1204, the conquest of large parts of the Byzantine Empire, and the foundation of the Latin Empire. The following year he was defeated at the Battle of Adrianople by Kaloyan, the emperor of Bulgaria, and spent his last days as a prisoner.
William II (1307 – 26 September 1345) was Count of Hainaut from 1337 until his death. He was also Count of Holland (as William IV) and Count of Zeeland. He succeeded his father, Count William I of Hainaut. While away fighting in Prussia, the Frisians revolted. William returned home and was killed at the Battle of Warns.
Ferdinand (Portuguese: Fernando, French and Dutch: Ferrand; 24 March 1188 – 27 July 1233) reigned as jure uxoris Count of Flanders and Hainaut from his marriage to Countess Joan, celebrated in Paris in 1212, until his death.
Henry III (c. 1140 – 21 June 1221) was the duke of Limburg and count of Arlon from 1165 to his death. He was the son and successor of Henry II and Matilda of Saffenberg.
In 1172, he fought against the count of Luxembourg, Henry the Blind, and then his ally, the count of Hainaut, Baldwin V. The environs of Arlon were devastated and the duke, overcome, had to recompense the count of Luxembourg for the wrongs he had done him. In 1183, he supported the election of Folmar of Karden as archbishop of Trier. This was opposed by the emperor, Frederick Barbarossa.