In an effort to win the crown of Britain, Brennius and Belinus waged war between each other to determine who should succeed their father.

Belinus called to arms all of Britain against Brennius and the two armies met in the forests of Calaterium.

Eventually, Brennius invaded Britain behind a massive Gallic army and met Belinus on the battlefield once again.

Their mother, however, convinced Brennius to make peace, and the two brothers ruled their two realms in harmony with each other.

According to the story, after a year of warfare, the joint army managed to submit all the Frankish kingdoms in Gaul to their authority.

Outside Rome the two consuls, Gabias and Porsenna, sued for peace and offered wealth, tribute, and hostages as a sign of their submission.

In the morning, Belinus attacked the Italians, who were not in armour and were unprepared for battle at that point in time.

When Belinus finally died, he was cremated and placed on top of a great tower he had created; he was succeeded by his son Gurguit Barbtruc.

The latter is a namesake of Lars Porsena, a King of the Etruscans who is believed to have fought against the recently founded Roman Republic around 500 BC.