In 1202, Francis took part in the Battle of Collestrada, a conflict between the cities of Assisi and Perugia. The defeat of the Assisians led to many fighters being captured, Francis among them. 

He remained a prisoner for almost a year. This experience of suffering and deprivation led him to reflect deeply on his life. Imprisonment was one of the first events that caused him to question his former dreams of wealth and glory.