Arthur I de Rennes
Duke of Brittany, Count of Rennes, Count of Vannes

The war between Anjou and Brittany ended in the imprisonment of Alain IV by the Armies of Anjou. County of Nantes was lost to Anjou and Alain IV was taken to the dungeons in Anjou. But he was still allowed to see his wife and interact with her. Many more children were born to Alain even though he remained in jail. And in 1118 at the age of 61 Alain IV passed away leaving Brittany to his eldest son Arthur I.
Arthur of course wanted revenge on Anjou but at the current state it was not possible. The realm was on the brink of another civil war after the death of Alain IV. But some how Arthur I managed to restore order and unite the lords of Brittany behind him. He also found out that the army of his late father had grown to match the armies of Anjou, lot of improvements had been made by the lords in the past few years and Arthur knew that having large army would bring Nantes back and maybe even more.

In 1121 Anjou decided to attack Brittany once again. Only this time Brittany was prepared to defend itself with all of her strength.

Anjou made a great mistake when it brought all of it's armies to siege the castle of Dol. While the armies of Anjou had been allowed to march to siege Dol, Arthur I had gathered all his armies to Vannes. From there here lead his armies to fight the besieging troops of Anjou in Dol. Anjou had lost many men while trying to take the reinforced castle of Dol and when the armies of Arthur arrived Anjou was outnumbered. The

Pierre I de Rennes
Duke of Brittany, Count of Rennes, Count of Vannes
Even though the battle of Dol was won by Arthur and his men, Arthur was not to see Brittany take revenge on Anjou as he was fatally wounded during the battle. In February he finally died of his wounds leaving Brittany to his three years old son Pierre.
