Really. More of this Manifest Destiny! Great Britian/Canada and USA sat down and peacefully talked where the lines should be drawn.
The British made promises to convince the Native Americans to be by their side. Some of the promises include trade and secure their land.
Mostly they affected it through their imperialism. They would colonize and take over countries for resources, and with them they would bring their technologies and things that they needed. After they left these things stayed, things like telephone and telegram lines and similar things. Culturally, they would mostly disregard the local culture and impose their own which would often be accepted and kept by the locals, but often there was also warfare.
Answer choices and Try peeranswers. I prefer it over this!