[2] Alan was the third son of Stephen, Count of Tréguier, and Hawise de Guingamp.
After Count Stephen's death in 1135/6, his Breton lands were inherited by his eldest son, Geoffrey Boterel II, whereas his English lands, the Honour of Richmond, went to Alan.
In part to promote the alliance with Conan III of Brittany.
After the Battle of Lincoln (1141), Alan was captured by Ranulf de Gernon, 4th Earl of Chester and tortured until he relinquished his claim to the Earldom of Cornwall.
With Bertha, Duchess of Brittany, he had three children: In addition, Alan had four illegitimate sons:[4] Alan died in Brittany by 1146 and was buried at Bégard Monastery.