The last ice age which ended 10,000 years ago created a land bridge over the Bering Strait between Asia and North America. This enabled early Homo Sapiens (humans) to wander onto and settle across both North and South America.
The Indians that settled around Calgary became the Blackfoot, Blood, Peigan, Sarcee (Tsuu T'ina), and Stoney bands. These Indians used to roam the plains and the eastern Rockies, but now reside in several reserves around the city.
The lands were first explored by fur traders working for the Hudsons Bay Company and the Northwest Company (which were later to merge). The first settler and rancher in Calgary was Sam Livingston who settled in the early 1870's after returning from the California Gold Rush of 1849.
Fort Calgary was built in 1875 by the NorthWest Mounted Police (later renamed the RCMP) to protect the western plains from American whiskey traders. The fort was originally named Fort Brisbois, after the first inspector of the NWMP. The Indians agreed to cede their land to the Canadian Government at the signing of Treaty No. 7 in 1877. The reserves are located as follows: Blackfoot near Gliechen, Blood Indians near Cardston, Peigan near Pincher Creek, Sarcee near Calgary, and the Stony near Morley.
More history of Calgary