Born in Sicily in the late 13th century, he was the grandson and successor of Blasco the Elder.
The Alagona family was the most powerful in Catania at first and then eastern and eventually, under Blasco II, all of Sicily.
In 1320, Frederick II of Sicily ceded the Castle of Aci, expropriated from Margherita, descendant of the Admiral Roger of Lauria, to Blasco.
Giovanni of Randazzo, brother of Peter, appointed him regent for his nephew, the young King Louis.
As regent, Blasco was opposed by Matteo Palizzi, lord of Tripi and Saponara and vicar of the realm.