Moose Factory, trading post, NE Ont., Canada, near the mouth of the Moose River on James Bay. A fort was built there by Charles Bayly, governor of the Hudson's Bay Company, in the early 1670s. In the struggle between the English and French in Canada, the fort changed hands several times and shortly after 1696 was destroyed. In 1730 the company built a post close to the ruins of the original fort. This post has been in continuous operation to the present day.