The region stretches northwards via the Spallumcheen Valley to Sicamous in the Shuswap Country, and reaches south of the Canada–United States border, where it continues as Okanogan County.

[5] An alternative explanation from Washington is ‘People living where you can see the top’, ostensibly of Chopaka Peak in the Lower Similkameen.

At the end of the Pleistocene, marginal lakes formed along the sides of the melting ice lobe and streams deposited their loads in them as deltas and accumulations of silt.

The Okanagan north of Kelowna has a humid continental climate (Köppen: Dfb) with warm, sometimes hot summers and cold winters with highs around freezing, though mild by Canadian standards.

Some regions of the Okanagan, most notably near Kelowna, border on an inland oceanic climate due to it having an average temperature slightly above −3.0 °C (26.6 °F) and below 0 °C (32 °F).

The Okanagan south of Kelowna has a semi-arid climate (Köppen: Bsk) with hot, dry summers and cool winters.

The southern Okanagan is dominated by northern reach of the Columbia Plateau ecoregion and is the only xeric shrubland ecosystem in Canada.

At the height of Okanagan culture, about 3000 years ago, it is estimated that 12,000 people lived in this valley and surrounding areas.

The Okanagan people employed an adaptive strategy, moving within traditional areas throughout the year to fish, hunt, or collect food, while in the winter months, they lived in semi-permanent villages of kekulis, a type of pithouse.

The trade route lasted until 1846, when the Oregon Treaty laid down the border between British North America and the United States west of the Rocky Mountains on the 49th parallel.

The Fraser Canyon Gold Rush of 1858 eventually encouraged more settlement as some prospectors from the United States took the Okanagan Trail route on their way to the Fraser Canyon, although at the height of the rush the American adventurers who used the route did not settle because of outright hostilities from the Syilx, whom a few of the parties traversing the trail had harassed and brutalized.

A few staked claims around the South Okanagan and Similkameen valleys and found gold and copper in places, with another trail from Fort Hope to newer goldfields at Rock Creek and Wild Horse Creek in the East Kootenay, skirting the US border and crossing Osoyoos Lake at Osoyoos, which was a customs post and also the location of the gold commissioner's office.

A mining industry began in the southern Okanagan region, with Fairview, now an empty benchland on the western side of Oliver, the best-known and largest of the boomtowns created in the later part of the 19th century.

While the last half-century has grown several resource-based enterprises in the region, primarily forestry, though mining had played an important role in earlier times.

The Osoyoos Indian Reserve leases large swathes of land to commercial vineyard developments and is where 40% of wine grapes used in the Okanagan come from.

The continued growth and operation of the agricultural industry in the Okanagan absolutely depends on the employment of temporary migrant workers.