After several years in which he served a probation in the monastery at Cnobheresburg, Ultan went off to live alone in East Anglia as a hermit. In around 643 Fursey handed his duties to Foillan and went to join Ultan, taking nothing with him, and they lived for a year together by the labour of their hands in a life of contemplation and philosophy. However the kingdom was disturbed by inroads of heathens, and Fursey left East Anglia in around 644, entrusting the monastery in East Anglia and its brethren to his brother Foillan. After being welcomed by Erchinoald at Péronne and by Clovis II and Queen Balthild, Fursey was granted an estate at Lagny on the Marne, where he built a monastery.