He first visited Minbar in January 2259 to learn about the culture and the martial arts of the Minbari. There he met the new Earth Ambassador Jeffrey Sinclair who became impressed with him and later invited him to join the Rangers.
After completing his Ranger training at Tuzanor he visited his brother at Arisia III where the family's mining colony was located, aboard a Minbari freighter. He wanted to buy Quantium 40, warn Marcus about the Shadows, convince him to join the Rangers or at least allow basing a Ranger listening post at his mining colony.
Marcus refused, but was happy to have William with him for some days, while they negotiated a constant supply of Q-40. Two days later, both brothers were making a space tour with a XO-Sphere when a Shadow Vessel appeared and destroyed the refinery and the colony. Marcus directed the Sphere to a emergency shuttle, but they crashed. Marcus survived the impact unharmed, but William was critically injured. Before he died, he asked Marcus to continue his work with the Rangers. Marcus promised him to do it, and barely escaped of the planet before the Shadow vessel attacked again. He managed to survive barely, but after being rescued, Marcus declaration was ignored, and the attack was forcibly classified an industrial accident. Marcus wanted to return to Arisia to recover his brother's body, but he believed it had been blown to bits in the explosion. Later, he joined the Rangers, fighting as one during the rest of the war, in memory of William.
William was the first known Ranger to die in action during the Shadow War.