 Dafydd ap Gwilym who flourished in the middle of the fourteenth century is considered by many to be the greatest of the Welsh poets.There were a number of rebellions including ones led by Madog ap Llywelyn in 1294-5  and by Llywelyn Bren, Lord of Senghenydd, in 1316-18.In the 1370s the last representative in the male line of the ruling house of Gwynedd, Owain Lawgoch, twice planned an invasion of Wales with French support.