'John I of Avesnes' (
May 1 1218 –
December 24 1257) was the
count of Hainaut from
1246 to his death. Born in
Houffalize, he was the eldest son of
Margaret II of Flanders by her first husband,
Bouchard IV of Avesnes. As the marriage of Margaret and Bouchard was papally dissolved, he was considered illegitimate.
His mother remarried to
William II of Dampierre and bore more children who could claim her inheritance. Thus, John and his brother
Baldwin undertook to receive imperial recognition of their legitimacy and did so from the
Emperor Frederick II in March
1243. On
5 December 1244, Margaret inherited
Flanders and
Hainaut and designated her eldest son by her second husband,
William III of Dampierre, as her heir. Immediately a war, called the
War of the Succession of Flanders and Hainault, was set off over the rights of inheritance, pitting John against William.
After two years of fighting, in
1246,
Louis IX of France intervened to settle the conflict. He granted Hainaut to John and Flanders to William. Nonetheless, conflict was reopened. In
1250, Margaret was forced to give over the government of Hainaut to John. On
6 June 1251, William was assassinated and it was shown that the Avesnes had financed the crime. On
4 July 1253, John defeated the armies of Margaret and her second Dampierre son,
Guy, at the
Battle of West-Capelle. Guy was imprisoned and Margaret agreed to sell her rights to Hainaut to
Charles of Anjou if he would reconquer it from John. John's brother-in-law
William II, Count of Holland, the elected ''
rex Romanorum'', was convinced to grant Hainaut (an imperial fief) and those Flemish lands within the Empire to John. Charles was defeated and King Louis, returning from the
Seventh Crusade, ordered his brother to abide by his arbitration of 1246. On
22 November 1257, Guy finally relinquished Hainaut, but John died on
Christmas Eve in
Valenciennes.
Family and children
He married
Adelaide of Holland in 1246 and had the following issue:
★
John II, Count of Hainaut and
Holland (1247-1304)
★ Joanna, Abbess of Flines (died 1304)
★
Bouchard,
Bishop of Metz (1251-1296)
★
Guy,
Bishop of Utrecht (1253-1317)
★
William,
Bishop of Cambrai (1254-1296)
★
Floris,
stadholder of Zeeland and
Prince of Achaea
See also
★
Counts of Hainaut family tree