In 1864, he brought Abbie Bonser to the area as his wife. Abbie was widely considered the most beautiful woman in the territory. Her looks and personality were described in great detail in the Seattle Post Intelligencer and repeated in the Oregonian at the time of her father’s death. (John Bonser)
William and Abbie ran a trading post in what was considered the heart of Squak Valley, (now Isaquah) Their only source of real income was from the sale of hoop-poles.
They employed the local Snohomish Indians to help manufacture and transport the hoop-poles. William not only trusted his employees, but felt they shared a solid friendship.
Against the advice of his neighbors, he often shared his liquor with his native friends. He never believed the stories he’d heard of bad effects liquor had on them, for in his heart he knew they were his friends and would never harm him or his family. The Natives, in turn, looked upon him as a “white” chief. He was truly respected by all.
Further up the Snohomish River there was a fracas between some settlers and local Native Americans. Three Natives were killed, including a chief. Though this created great unrest among the neighboring tribes, nothing happened until the following summer.
Against the advice of fellow settlers, William still shared his liquor with his friends/employees. One evening they all got “gloriously” drunk. Two of the Snohomish tribesmen who worked for William Casto decided, in their drunken state, revenge was necessary. They needed to avenge the death of their fellow tribesman. William, as a “white” chief, was an appropriate victim.
One evening, as William, Abbie and a neighbor were sitting down to dinner, the two Snohomish employees ambushed and killed all three. A Klickitat Indian named Aleck, having heard the shootings, rushed to their aid. Although he was too late to save the Casto’s and their friend, he was able to kill the two who committed the murders. This further enraged the Indians. Now they needed to avenge the deaths of the ones who had been murdered by Aleck. They chose Aleck’s young son.
For weeks following the incidents the local papers were filled with stories of the evil effects of liquor.
(Information from family stories and material shared with us by Jean Erickson.)