Land Back, also referred to with hashtag #LandBack, is a decentralised campaign that emerged in the late 2010s among Indigenous Australians, Indigenous peoples in Canada, Native Americans in the United States, other indigenous peoples and allies who seek to reestablish Indigenous sovereignty, with political and economic control of their ancestral lands. Activists have also used the Land Back framework in Mexico, and scholars have applied it in New Zealand and Fiji. Land Back is part of a broader Indigenous movement for decolonisation.

The United States government illegally seized the Black Hills – a mountain range in the US states of South Dakota and Wyoming – from the Sioux Nation in 1876. The land was pledged to the Sioux Nation in the Treaty of Fort Laramie, but a few years later the United States illegally seized the land and nullified the treaty with the Indian Appropriations Bill of 1876, without the tribe's consent. That bill "denied the Sioux all further appropriation and treaty-guaranteed annuities" until they gave up the Black Hills. A Supreme Court case was ruled in favor of the Sioux in 1980. As of 2011, the court's award was worth over $1 billion, but the Sioux have outstanding issues with the ruling and have not collected the funds.