Tsilhqot'in (Chilcotin) baskets are from the western Subarctic region of North America, in the interior of nothern British Columbia. The Tsilhqot'in people speak a Northern Athapaskan language, and have been strongly influenced by Plateau culture. (Some authorities classify them in the Plateau rather than the Subarctic culture area.) They made coiled baskets with all-over imbricated designs. The baskets were often reinforced with willow hoops sewn at the top edge for strength. An undulating rim on the basket is typical and resembles the shape of some birchbark containers from this area. Animals, figures and geometric designs in bands are worked into the design in bullrush and cherry bark on cedar root.

You are right, your basket was made by a Tsilhqot'in weaver!
Now try to identify the shape and use of your basket.