Te Rarawa and Ngati Haua trustee Richard Murray said great sacrifices had been made over many years to ensure the return of the land.
"We're keen to protect these lands and look at development options for future generations to come, and ensure that the whenua is secured in a way that it can never be put at risk again," he said.
Te Runanga o Te Rarawa chairman Haami Piripi said Whakakoro could not be included in the tribe's Treaty settlement because it was technically private land.
However, now that the iwi had settled its historical claims, it could buy the land and preserve it for the future of Ngati Haua and Te Rarawa.
Once the previous owners, the Van den Brink Group, understood the importance of the land to Ngati Haua they had "bent over backwards" to help.
"They could have sold it out from under us but they saw an opportunity to do something for the community.
"That was reflected in their patience and the price," Mr Piripi said.
Te Rarawa and Ngati Haua representatives would meet in the New Year to discuss the ownership and management of Whakakoro, he added.
The first priority would be to come up with a management plan that was mana-enhancing, protected ancient burial sites, and allowed the land to pay for itself, creating jobs and returning Whangape to the prosperity it once enjoyed.
Te Rarawa's ownership of three more large farms would allow economies of scale, although Whakakoro would not necessarily remain a sheep and beef farm only.
Mr Piripi said the basis for the tribe's settlement had always been He whenua riro atu, he whenua hoki mai. (Land lost is the foundation of land that should be returned). That had been fulfilled with the purchase of Whakakoro, which also honoured forebears such as Glass Murray.
"I'm just pleased for the old fellows who held on to their claim and passed on without seeing it resolved. Before he died Glass made us younger ones promise to do our best to get the mountain back. I think he'd be pleased," he said.
Mr Piripi said the purchase showed what iwi and hapu could achieve when they worked together.
That was especially relevant given the current divisions between Ngapuhi iwi and hapu over their Treaty settlement.