Dakota Tipi First Nation and Canupawakpa Dakota First Nation have filed a lawsuit in Winnipeg’s Court of King’s Bench alleging that Manitoba and the federal government have benefited from oil and gas revenues drawn from land they describe as unceded Dakota territory. The claim centres on the mineral-rich Williston Basin in southwestern Manitoba, a region that supports all of the province’s oil extraction and generates billions in annual activity linked to petroleum development.

Court documents state the Dakota were excluded from treaty-making in the region and maintain they never relinquished their interest in the land or its subsurface resources. The filing argues that land transferred by the Crown should have included mineral rights and that both levels of government failed to uphold constitutional and fiduciary duties by managing those resources without Dakota consent or compensation.

The nations have previously pursued legal action over other properties, including a former air base near Portage la Prairie now operated as Southport Aerospace Centre. Those filings contend that the land was taken without proper consultation, forming part of a broader pattern of disputes involving historical occupation and federal management of public sites.

The new case seeks recognition of Aboriginal title over the Manitoba portion of the Basin or financial compensation equivalent to what the nations say would have been received had their rights been acknowledged. The matter adds to a growing list of land and resource challenges launched by Indigenous communities across the country, increasing uncertainty for governments and industries operating in contested areas and raising unresolved issues about how future property, development and jurisdiction may be shaped.