The Grand Council of the Crees (Eeyou Istchee) or the GCC(EI) (ᐄᔨᔨᐤ ᐊᔅᒌ in Cree), is the political body that represents the approximately 18,000 Crees or “Eeyou” ("Eenou", Inland dialect) of the territory called Eeyou Istchee ("The People's Land") in the James Bay and Nunavik regions of Northern Quebec, Canada.
 The Grand Council has twenty members: a Grand Chief and Deputy-Grand Chief elected at large by the Cree people, the Chiefs elected by each of the ten communities, and one other representative from each community.
Eeyou Istchee (Cree: ᐃᔨᔫ ᐊᔅᒌ / ᐃᓅ ᐊᔅᒌ, meaning "The People's Land") was a territory equivalent to a regional county municipality (TE) of Quebec, represented by the Grand Council of the Crees.
 On July 24, 2012, the Quebec government signed an accord with the Cree Nation that result in the abolition of the neighboring municipality of Baie-James and the creation of a new regional government known as Eeyou Istchee James Bay Territory.
The Cree Nation of Nemaska is a Cree First Nation of Quebec, Canada.
 It is headquartered at the Cree village of Nemaska and also has a "terre réservée crie" of the same name, both located in the Eeyou Istchee territory in Northern Quebec.
 In 2016, it has a registered population of 781 members.
 The nation is in negotiation with the government of Canada to obtain its self-governance.
Lake Nemiscau (in French: "Lac Nemiscau") is a freshwater lake, located in the municipality of Eeyou Istchee James Bay, in the administrative region of Nord-du-Québec, in north-western Quebec, in Canada.
 The lake Nemiscau is crossed by Rupert River.
Eeyou Istchee James Bay Territory (French: Gouvernement régional d’Eeyou Istchee Baie-James , Cree: ᐄᔨᔨᐤ ᐊᔅᒌ ᒉᐃᒥᔅ ᐯᐃ ᐊᔅᒌᐤ ᑎᐹᔨᐦᒋᒑᐎᓐ ) is a territory equivalent to a regional county municipality (TE) in the administrative region of Nord-du-Québec.
 On July 24, 2012, the Quebec government signed an accord with the Cree that resulted in the abolition of the local municipality of Baie-James and the Cree Eeyou Istchee TE to create the a new and combined TE of Eeyou Istchee James Bay Territory.
Jamésie was a territory equivalent to a regional county municipality (TE) of Quebec, Canada.
 It has been replaced by the Eeyou Istchee James Bay Territory, which was formed out the Jamésie and Eeyou Istchee territories.
Waskaganish (Cree: "ᐙᔅᑳᐦᐄᑲᓂᔥ/Wâskâhîkaniš" , Little House) is a Cree community of over 2,200 people at the mouth of the Rupert River on the south-east shore of James Bay in the Eeyou Istchee territory in Northern Quebec, Canada.
 Formerly called Fort Rupert, the location is one of three original Hudson's Bay Company posts on James Bay, the other two being Fort Albany on the west shore, and Moose Factory on the south.
The Cree (Cree: Nēhiyaw ; French: "Cri" ) are one of the largest groups of First Nations in North America, with over 200,000 members living in Canada.
 The major proportion of Cree in Canada live north and west of Lake Superior, in Ontario, Manitoba, Saskatchewan, Alberta and the Northwest Territories.
 About 38,000 live in Quebec.
Lake Evans is a freshwater lake in the municipality of Eeyou Istchee James Bay, in the administrative region of Nord-du-Québec, in western Quebec, Canada.
 This lake is crossed by the Broadback River.
Chisasibi (Cree: "ᒋᓵᓰᐲ/Cisâsîpî" meaning Great River) is a village on the eastern shore of James Bay, in the Eeyou Istchee territory in northern Quebec, Canada.
 It is situated on the south shore of La Grande River (the Grand River), less than 10 km from the river's mouth.
 Chisasibi is one of nine Cree villages in the region, and is a member of the Grand Council of the Crees of Quebec.
 The territory surrounding Chisasibi is part of the Municipality of Baie-James, of which parts are jointly managed with the Cree Regional Authority.

Question: Which First Nations group of over 200'000 members living in Canada signed an accord with the Quebec government, leading to the creation of Eeyou Istchee James Bay Territory?
Answer: The Cree