Guillaume I de Coucy

Sir Guillaume I de Coucy (died 1335), Lord of Coucy, Oisy, La Fère, Marle and Montmirail was a French nobleman.
Biography.
Guillaume was the son of Enguerrand V de Coucy and Christine de Lindsay.
Marriage and issue.
He married secondly Isabelle, daughter of Guy IV de Chatillon and Marie de Bretagne, they are known to have had the following known issue.