 At the age of five he entered the Abbey of Reichenau, on an island in the Lake of Constance.Abbot Waldo (786-806) made him head of the monastic school, and in this capacity he did much for the instruction and classical training of the monks, as well as for the growth of the library.When Waldo was transferred to the Abbey of St. Denis, near Paris, in 806, Haito was made Abbot of Reichenau, and about the same time Bishop of Basel.