The Hurricanes have apologised for offence caused by referring to an upcoming rugby game against the Chiefs as the 'Taranaki Land War'.
The post was heavily censured by the public including by former Māori Party co-leader Marama Fox, and it has since been deleted.
Ms Fox said it was a "sad indictment on our country's progression" that the Hurricanes saw no red flags before posting the promotion.
A Hurricanes spokesperson said the post was only intended to be a reference to the game, and the person who made the post had no idea of the history they were invoking.
"The promotional department had no idea of the reference, and when we were made aware we've taken the post down," the spokesperson said.
"If anyone has taken offence we apologise, it was a sincere mistake."
The team issued a public apology on Wednesday afternoon, which said:
"The Hurricanes acknowledge we have made a genuine mistake in regards to a promotion for Friday's match against the Chiefs by referring to a Taranaki Land War. Firstly we have unreservedly apologised to Taranaki whānui and Waikato Tainui iwi for any offence we caused. To our fans and supporters this does not reflect the views and values of the Hurricanes family, our players and coaches. We are sorry."
Ms Fox said the incident is a sign of a country that does not know its own history, and that's why her party had pushed to have the New Zealand Land Wars recognised.
"People are inadvertently making blunders like this because we don't teach it in our schools, so people don't understand how offensive it is."
She said that consecutive Governments had refused to acknowledge the treaty, Māori culture, history, and language.
Ms Fox said the blunder further emphasised the point that film director Taika Waititi has made about racism in New Zealand.
"If we would only acknowledge our own history, it would alleviate the institutional racism that is precisely what Taika is talking about."
Ms Fox felt hopeful that New Zealand was continuing to grow up as a nation, and in particular younger generations were more inquisitive about learning about Māori culture and wanting to learn Te Reo.
"It's part our growing up that we learn from our mistakes," she said.
The Māori Party also called for a national day of commemoration on November 5 for the historical injustice at Parihaka in 1881, when the Crown invaded the Taranaki community after years of peaceful resistance to land confiscation.
The Te rā o Parihaka bill in Ms Fox's name was never drawn, but has since been taken up by Green co-leader Marama Davidson.