Isan

Saint Isan was a saint of the 6th century in south Wales, patron of Llanishen in Cardiff. He is said to have been a follower of the Celtic teacher Illtud.

In the year 535, with Saint Edeyrn, he went eastward from the small religious settlement of Llandaff to found churches in the area around Caerphilly mountain. The sites they chose had good water from the Nant Fawr stream. In 537 Isan founded a settlement that later became known as Llanishen. The church of Saint Isan was built on the foundations of a 12th-⁠century church. His companion Edeyrn is said to have traveled widely, and for this reason churches in north and south Wales are dedicated to him; he gathered a community of about three hundred at Llanedeyrn. Isan is remembered in the churches of Llanishen in Monmouthshire and in Cardiff. He is honored as a saint of the undivided Church.