Complex sentence: Around 1793, in response to attacks by well-armed Cree and Assiniboines, large groups of Gros Ventres burned two Hudson's Bay Company trading posts that were providing guns to the Cree and Assiniboine tribes in what is now present day Saskatchewan.
Split into simpler sentences: Around 1793, in response to attacks by well-armed Cree and Assiniboines, large groups of Gros Ventres burned two Hudson's Bay Company trading posts. These trading posts were providing guns to the Cree and Assiniboine tribes in what is now present day Saskatchewan.