She was married twice, firstly to Geoffrey of Briel, Lord of Karytaina and then secondly to Hugh, Count of Brienne, having children only with her second husband.

Her father Guy was created Duke of Athens in 1260 by King Louis IX of France.

[citation needed] Isabella was married firstly in 1256 to Geoffrey of Briel, Lord of Karytaina.

[2] The couple were married for thirteen years however, no children were born in this time.

Through Isabella, her son Walter was able to claim Duchy of Athens in 1308 upon the death of his cousin Guy II de la Roche.