Einion Frenin was credited with the establishment of the original church at Llanengan, St Einion's. [1] The present church there, which was erected in the late 15th or early 16th century, [2] had a gilt and crowned statue of him prior to the Reformation [14] and bears Latin inscriptions reading Æniani Rex Wallie and Rex Walliæ ("Einion, king of Wales"). Miraculous locations nearby include Ffynnon Engan ("Einion's Well") and Ol Troed March Engan ("The Hoofprint of Einion's Horse"), a petrosomatoglyph near Castell Cinan whose collected rainwater was claimed to possess curative powers. [1] Other placenames possibly related to the king are Ogo' Engan ("Einion's Cave"), Bryn Engan ("Einion's Hill"), Caer Engan ("Engan's Camp"), and Croes Engan ("Einion's Cross"), a farm in Denbighshire. [1]
Llandogo in Monmouthshire was also sometimes previously known as Lann Enniaun ("Llanennion") and the bard Hywel Rheinallt composed a cywydd to the "golden-handed" Saint Einion in the late 15th century, recording another (now unknown) church in Gwynedd dedicated to St Einion. [1]