BBC's Garry Fletcher attended the ceremony

The constitutionally-binding treaty in the province of British Columbia - the first to be signed in modern times - gives the Nisga'a full title to about 2,000km-sq of land, a US $140m cash settlement and powers of self-government.

Ceremonial dancing by the tribes younger members

It also guarantees fishing and logging rights and the return of many historical cultural artefacts held in museums across Canada.

In return, the Nisga'a of the Nass Valley have agreed final settlement of all their claims and will also begin paying taxes.

The agreement was signed at a colourful and emotionally-charged ceremony held in the isolated Nass Valley, the homeland of the Nisga'a.

To the sound of shouting and drumming, Nisga'a leader Joseph Gosnell called it a triumph for his people.

Criticism from all sides

But critics say the deal is unaffordable and racially divisive. Some members of the Nisga'a also say their leaders have given up too much.

The treaty was agreed in principle two years ago but it has taken two years to work out the details.

It must now be approved by the nearly 5,500 Nisga'a, Canada's Parliament and British Columbia's provincial legislature.

Long struggle

The Nisga'a were among the first indigenous groups to claim redress for lost land.

But their petitions were ignored for more than 100 years until 1973, when Prime Minister Pierre Trudeau recognised Canada's obligations.

The treaty establishes a Nisga'a government, with broad control over public order, education and health, and a lower court system.