Very little is known about St. Manchan. He died of the plague in 664, composed a poem of which two lines survive, and may have been the author of a commentary, parts of which are quoted in an early twelfth-century manuscript (British Museum, Harley 1802). But though various attempts were made to establish his genealogy, there were other saints of the same name, so that the references to him are sadly confused, and all that is certain is that he lived in the first half of the seventh century, and gave his name to the place now called after him Lemanaghan, i.e., Manchan's grey land (Manchan's church). This was a small monastery in co. Offaly that has little recorded history and can never have been a house of much importance. In 1531 it was under the charge of the prior of the neighbouring monastery of Gallen, and by the beginning of the seventeenth century it was almost unknown, being described at that time as situated in the middle of an impassable bog. Its chief treasure, the shrine, attracted no notice from the outside world; but it was still preserved there, and there is a record of its existence in the church at Lemanaghan about 1630.