When the riding was created, the bulk of its population was in the Cariboo goldfields district around Barkerville, although its boundaries extended to the Yukon boundaries - the original Cariboo riding at its creation included all of the former New Caledonia fur district, north of those parts of it now in the Lillooet Land District which formed the Lillooet riding.¹ As mining exploration and other settlement spread northwards from the Cariboo mining areas, the Omineca, Fort George and Peace River ridings were split off by the end of the 19th century, and the Cariboo riding was reduced to the Cariboo Plateau, south from Quesnel to just south of Williams Lake and 150 Mile House, and including the Barkerville, British Columbia region as well as the remote Chilcotin region, which had no voting (settler) population when the riding was formed other than isolated traders and trappers who may have had time or means to vote. Nearly all of the 785 voters in the first election were in the goldfield towns, Quesnel (then Quesnellemouthe), Williams Lake or towns and ranches south along the Cariboo Road and other routes of the era, and those along the West Fraser from the Chilcotin River, including the Gang Ranch south to just north of Big Bar, an isolated canyon ranching, river-crossing and wagon-trail town in the Fraser Canyon, which was in the Lillooet riding.

Following the construction of the Canadian Pacific Railway (CPR), increased settlement on the Cariboo Plateau south of the goldfields region shifted the population weight of the riding to that area, which was increasingly centred on the town of Williams Lake and the plateau between there and Kamloops, British Columbia. The southern Cariboo region, later added in a redistribution and division of the Cariboo riding into Cariboo South and Cariboo North, which exist today, was originally part of the Lillooet riding. The Lillooet and Cariboo provincial ridings combined formed the original definition of the Cariboo federal riding.

¹ New Caledonia's southern boundary was vague, but it was generally accepted to include the Thompson area although its heartland is the Fort Saint James-Fraser Lake region northwest of Prince George.

When the riding was created its boundaries stretched from the Quesnel Lake and Chilcotin areas, flanking the great plateau of central BC on its east and west, all the way north to the Yukon border. At that time, although irrelevant to the issue of electoral representation, the riding's population included members of the Shuswap, Carrier, Chilcotin, Sekani and other more northerly nations. As the riding was reduced to roughly correspond with the Cariboo district (excluding Lillooet-Ashcroft, which were in the Lillooet electoral district, at least until the mid-20th century) the native population became only Shuswap, along the Fraser and east of it, and the Chilcotin people, who lived to the west of it. First Nations people, even in the reduced riding area, mostly outnumbered the total figure for non-natives until the early 20th century, but were not allowed to vote or run for office.

• Alexander Edmund Batson Davie, became the eighth premier of British Columbia
• Alex Fraser, held the seat for 20 years

Note: Winners of each election are in bold.

• Elections BC website - historical election data