Alidosio Alidosi della Massa

Alidosio Alidosi, known as Alidosio della Massa, founded the Castel del Rio branch of the Alidosi, the dynasty that ruled Imola. He was the first signore of Castel del Rio, then called the Massa di Sant'Ambrogio, a fief granted his ancestors by Emperor Otto IV.

In 1304 he served the Florentine Republic as capitano del popolo. He died after 1304 and was succeeded by his son Gentile; another son, Guido, carried on the line.