The line of succession of the counts of Champagne had become complicated in the current generation. Before he left France to fight in the
Third Crusade in 1190,
Henry II had his barons swear that should he never return, his younger brother
Theobald III was his designated heir. Henry II never returned from the Latin East, but instead married Queen
Isabella I of Jerusalem and fathered two daughters,
Alice and Philippa. Henry II died in 1197. Technically, Henry II's young daughters were his rightful heirs. However, their family made no attempt to press their claim, and Theobald III succeeded him. Theobald died of a sudden illness in May 1201, leaving behind his heavily pregnant wife,
Blanche of Navarre, who secured the succession for a
posthumous son,
Theobald IV. Having successfully married Philippa, Erard of Brienne-Ramerupt returned to Champagne with his new bride in January 1216. Armed clashes soon broke out, and the
War of Succession of Champagne began. King Philip II imposed a truce in April 1216 to put a stop to the fighting, and held a court at Melun in July 1216 to hear Erard and Philippa's case. Unfortunately for Erard, the court ruled that because Theobald III had already done homage for Champagne to the king for several years, yet Philippa and her family never challenged his succession in all that time, Henry II's daughters could no longer make a claim for the inheritance. Blanche again presented the signed agreements of Henry II's barons which swore that Theobald III was to be his heir if he never returned from the crusade. Unsatisfied, Erard returned to open rebellion in spring 1217. Erard gathered to himself a large number of barons from the fringes of Champagne or from old and powerful aristocratic families, who were not pleased with the increasing efforts of Theobald III and Blanche to bring them all under centralized control. Most of Erard and Philippa's supports came from the fringes of Champagne, along the southern and eastern borders, away from the core territories of "Champagne and Brie" in the west. One of Erard's major supporters was
Simon of Joinville, hereditary seneschal of Champagne and leader of one of the most powerful noble families in the county. Further, Erard allied with
Theobald I, Duke of Lorraine, significantly bolstering the rebel faction. By 1218, however, the tide had turned, as Blanche secured papal excommunications against the rebel lords, and gained the support of the neighboring duke of Burgundy and count of Bar. Further, Blanche allied with
Holy Roman Emperor Frederick II to counterbalance Duke Theobald I of Lorraine. By May 1218 Blanche and her army rode with Frederick II's forces to Lorraine's capital of Nancy and burned it to the ground. By June 1218, the rebellion had largely collapsed and individual lords began to make their own separate peaces. Erard and Philippa established a truce agreement in July 1218, which ultimately lasted the rest of Blanche's regency until 1222, during which time other rebel lords continued to haggle for better peace terms. Blanche offered peace on generous terms to Erard and Philippa, wanting to end the challenge to her son's rule as quickly as possible. Erard received a surprisingly large payment of 4,000 livres, with a lifetime rent of 1,200 livres. Only after the war ended, when hope of becoming count of Champagne was lost, did Erard stop the charade of presenting himself as "Erard of Brienne". Instead, after 1222, he would specify in his letters that he was "Erard of Brienne, lord of Ramerupt". ==Later life==