The Ngati Kahungunu Iwi Inc chairman said his great-grandfather and William Nelson had been peers "and even though they faced adversity during that time they worked together on a few things ... employment, education, and building a couple of churches called St Matthews".
"It was a special moment in history that is put into the current context."
Mr Tomoana said Mr Nelson had arrived in the area as Henare attempted to retain "the 20,000 acre fertile Heretaunga Block" of which he was the principle owner.
"As they were leaving Hastings Henare was issued with a summons for unpaid bills. He and his troop continued and were hailed as national heroes in the ensuing battle but while away a court hearing was held ruling against Henare.
"He did not receive payment for the military hardware as he was entitled and eventually lost Heretaunga."
The two were peers as William Nelson created the Tomoana (or Nelson Brothers) freezing works which employed local Maori, Henare began a commission of inquiry into illegal land sales, began printing a newspaper, and established a Maori Parliament at Waipatu.
As well as commemorating this relationship, Mr Tomoana said the title of Hawke's Bay Showgrounds Tomoana would bring provenance to the region, and would mean they could become more involved with events at the venue.
"We can assist with provenance, and product, and authenticating product, and adding a bit of cultural texture to everything that happens there," he said.
"Without the name it was always undercover, but now we can be a lot more overt about it.
"We've always been supported but we didn't see how we could really get involved. Getting the name changed like that we're suddenly totally involved, we'll put a cultural texture to the whole thing."
The change would also benefit Ngati Kahungunu - "we're back as part of the brand now".
"I think it's great for Hawke's Bay but especially great for Kahungunu."
Mr Tomoana said they would also be able to have economic, and pastoral input. As they now owned "a whole lot of farms ... we're quite an economic force in the primary industries now too."
"So where we may have not participated before, we may now be more enthusiastic about it."
Today, the showgrounds also includes the adjoining area of Waikoko - about a decade ago the waterway within Waikoko Gardens was identified as being wahi tapu (sacred site), as it symbolised the many springs which had once flowed through in the showgrounds area.