He was the son of James of Avesnes, and Adèle, lady of Guise.
[1] Walter fought alongside Count Ferdinand of Flanders at the Battle of Bouvines in 1214,[2] then left to fight in the Holy Land.
Taken prisoner, he was ransomed by the Knights Templar and helped construct the Pilgrim Castle, in 1218,[3] donating 1,000 Saracen bezants towards its construction.
[4] With the income from Guise lands, he began work on modernizing his castles.
He also built a castle Englancourt to control the road through the county of Hainaut.