He therefore returned to Ferrara, considerably burdened with debts; and this was just the time at which Tasso's mental derangement began to manifest itself.

Between 1575 and 1579, the date of Tasso's imprisonment at Sant' Anna, the two men lived together at the Court.

Guarini's rivalry induced him at this period to cultivate poetry with such success that, when the author of the _Gerusalemme_ failed, Alfonso commanded him to take the vacant place of Court poet.

There is an interesting letter extant from Guarini to his friend Cornelio Bentivoglio, describing the efforts he made to comply with the Duke's pleasure.

'I strove to transform myself into another man, and, like a playactor, to reassume the character, manners and emotions of a past period.