Franis Kirwan, who was appointed in 1645, is the only Killala bishop who had a biography written of him, by his nephew, and it gives a good insight into the diocese in the middle of the seventeenth century. He was one of the four bishops representing the Irish bishops at the Confederation of Kilkenny. He introduced a small catechism and had plans to set up a craft school. But then Cromwell came and the bishop lost his residence in Killala and went into hiding in a mice-infested room where he said Mass on a chest. Later he returned in disguise to his native Galway . In June 1654 he was taken into custody with thirty priests and after fourteen months he was deported to Nantes.