In order to avoid military service Courtenay paid a fine on 12 December 1276.
He was called to arms on the emergency against the Welsh princes, fighting in the 1282 campaign.
In 1284, he came into possession of The Abbey, Sutton Courtenay, which he first leased to Solomon of Rochester.
[5] Courtenay married Eleanor le Despenser (d.1328),[6] daughter of Hugh le Despencer, 1st Baron le Despencer, Justiciar of England, of Loughborough, Leicestershire and Ryhall, Rutland by his wife Aline Basset, daughter of Sir Philip Basset, Justiciar of England, of Wycombe, Buckinghamshire and Compton Bassett and Wootton Bassett, Wiltshire.
By his wife he had four[6] sons and five[6] daughters:[7] Courtenay died at Colcombe, Devon, on 28 February 1292.