He came from:
Marignano; he was good looking, tall and solid, full of good sense and very devout. He was one of the most beloved brothers of Francis and travelled with him to France, Rome, Siena and Perugia. He was his confidant and was present at various ecstasies of Francis. In a spirit of obedience he was the gate keeper, went begging and worked in the kitchen. He was the ambassador Francis sent to Silvestre and Clare.

His life:
“… a man of great holiness and discernment and grace in speaking about God, because of which St Francis loved him much…” (The Little Flowers of St Francis, Chap X p. 62) he figures in a beautiful chapter of the Flowers, when Francis is visited by an Angel, who asked Masseo to call Elia and then appeared to Bernard who was not physically present with them but was on his way back from Santiago (Flowers, Chap IV pp. 50-52). Another lovely chapter in the Flowers is the IXth, when Masseo asks Francis why everyone wants to follow him: “Say, why is it that all the world seem to be running after you, and everyone seems to want to see you, and hear you, and obey you? You are not a handsome man, you do not have great learning or wisdom. You are not a nobleman. So why is all the world running after you?”. St Francis gives a wonderful reply: “You want to know why after me? You want to know why after me? You really want to know why all the world is running after me? I have this from the all-holy eyes of God, that see the good and the evil everywhere. For these blessed and all-holy eyes have not seen among sinners anyone more vile, or insufficient than I am. And so in order to do that wonderful work which He intends to do, He did not find on earth a viler creature than I…” (Flowers Chap IX p. 63).
Another moment in their “pilgrimages” is that in which Francis and Masseo are at a crossroads and cannot decide which path to take. Francis makes Masseo turn round and round and when he stops says: “That is the way God would have us to go” (Flowers Chap. XI. P. 64)
At Cannara he was present when Francis preached to the birds.
He also helped Rufino when the latter had a moment of great inner torment (Flowers Chap. XXIX p. 113).
He accompanied Francis to Perugia to meet Pope Honorius III and ask his Indulgence for the Portiuncola (the Pardon of Assisi).
He was living in La Verna when Francis received the stigmata and Francis recommended the mountain to him and to Angelo.

Of him Francis said:
when he was delineating the perfect friar by stringing together the characteristics of some of the brothers, that he should “… have the pleasant aspect and good sense of Masseo, with his devout and beautiful way of speaking…” (The Mirror of Perfection 85/1782).
Francis called him “his companion” (Flowers, Chap XIII p. 67).

He is buried:
since 1932 in a small urn in the crypt of St Francis to one side of his tomb: his travelling companion for ever.