Balduin was the first Duke of Brionne and the fifth of the Grail Companions of Gilles le Breton during the Twelve Great Battles that freed and unified Bretonnia. In the glory of the charge was Balduin most alive, and whilst others more tempered by the fires of war better controlled their ardour, he was ever in the forefront of battle.
Balduin became the lord of Brionne in 930 IC, when his father died in a duel against the lord of Quenelles over the ravaged lands of Cuileux. Two years later, he led his horsemen to victory against the Orcs.
Balduin joined the Grail Companions of Gilles le Breton when the lords of Bastonne, Mousillon, Lyonesse, Bordeleaux and Aquitaine came to his aid during the third of the Twelve Great Battles. Just as the Bretonni armies struck the rearguard of the Greenskins besieging Castle Brionne, Lord Balduin sallied forth across his oaken drawbridge with the last of his knights. He smote down the largest of the enemy Warbosses, but not before his adversary's massive axe became embedded deep in his shield. Such was the strength of the blow that the weapon could not be removed, but Balduin fought on for the remainder of the day bearing the immense burden without faltering. From then on, the battle-axe would be the heraldic sigil of Brionne. Though they were greatly outnumbered, the Bretonni tore through the greenskins like a scythe through wheat in harvest, and Gilles and Balduin met in the midst of the battle. They clasped forearms as brothers, and Balduin was joined into the number of the Companions.
Lord Balduin distinguished himself particularly during the Eighth Great Battle, as he rode before the Companions in a fury like a Norscan berserker, cutting the heads of a dozen shamans with his axe.
After the securing of all the lands of the Bretonni tribes, a great meeting took place in the home of Folgar of Artois. Here, the formal dukedoms were created, and the Bretonnian calendar was introduced - thus, year 979 of the Imperial Calendar is considered year 1 of the Bretonnian one. Each of the great lords of the Bretonni, the fourteen Grail Companions, including Gilles le Breton, were named Dukes. The Dukes swore oaths of allegiance, and Bretonnia was formed.