But the Herald understands since then, he has publicly made more racist remarks that didn't reflect the council's views.
It came to a head on Monday when Rimmington held an informal meeting with councillors after further complaints were made about his behaviour.
A source told the Herald that when councillors asked him to elaborate on the details of the complaints, he wouldn't give details.
Later that afternoon, eight councillors agreed he needed to go.
The majority of councillors didn't think he would reflect council's views, disrespected other councillors and had not learnt from his previous mistakes, an insider told the Herald.
Representatives of the group yesterday gave Rimmington a signed letter saying he had until Friday to leave on his own accord otherwise they would begin the formal process of removing him.
The elected members who signed the letter are deputy chair Kataraina Hodge and councillors Angela Strange, Jennifer Nickel, Denis Tegg, Stu Kneebone, Andrew MacPherson, Tipa Mahuta and Fred Lichtwark.
Rimmington did not appear surprised when handed the letter and said he would talk it over with his wife Edwina before making a decision, a source said.
Councillor Andrew Macpherson confirmed he had signed the letter because it was in the best interest of council.
"We are high performing and want to be led by someone who has got the skills that Russ doesn't currently demonstrate."
Macpherson's reasons for wanting Rimmington moved as chair were not due to one single thing, but a "whole range of matters".
He said he was one of the councillors who gave him a second chance in December, but he did not think Rimmington had delivered on their expectations.
Councillor Fred Lichtwark said he voted to have him removed because he wasn't representing council's views, just his own. He also didn't like the way Rimmington treated him personally and thought he was a divisive politician.
But councillor Stu Husband disagreed and said he was "absolutely disgusted" by the process going on.
"It's just a bunch of first-term back bench councillors."
He supported Rimmington as chair and said the six councillors who hadn't signed it were senior councillors and all chaired committees.
Husband had spoken to Rimmington who told him he felt blindsided and believed he had genuinely done a good job as chairman.
"If this is the way New Zealand politics is going then god help us.
"He will fight it - all the way."
Rimmington only has five months left of his term before the next local government elections. Unlike territorial authorities, the regional council chairperson is chosen by fellow councillors not the public and their appointment usually follows a lot of horse trading for positions such as committee heads.
In December, Rimmington was formally censured by his council for racist comments and told he needed to better perform on their behalf.
Rimmington found himself in hot water after blaming Māori for "usurping and jeopardising" the future development of the country at a Local Government New Zealand Three Waters webinar at the end of October.
The council formally recorded its concerns about his racist remarks and asked him to reflect on his responsibility as chair and his expectations, apologise to all involved and for all councillors to gain a better understanding of the Treaty of Waitangi.
But in an interview with Newsroom at the end of last month, Rimmington didn't appear to show any remorse saying he was still "giving bloody apologies, left, right and centre". He went onto say the proposed iwi-local government would be "dangerous" and "disproportionate" because iwi only represented 17 per cent of the population.
He has also been on the receiving end of the most code of conduct complaints in 2021 after fellow councillor Fred Lichtwark laid eight complaints against him relating to his comments and processes followed. The cost of the investigations - some of which are still ongoing - have cost ratepayers more than $9000 so far.
The Herald contacted all the signatories and Rimmington for comment. Kataraina Hodge was unavailable before deadline and Tipa Mahuta and Denis Tegg declined to comment. Angela Strange, Stu Kneebone, Jennifer Nickel and Rimmington did not respond to the Herald's requests.
Waikato Regional Council chief executive Chris McLay told the Herald he had not received any formal approach regarding removing Rimmington as chairman and staff advice had not been sought. However the Herald understands he was aware of the initial letter.
Under the Local Government Act a chairperson can be removed by a resolution of council or a requisition in writing signed by the majority of members at least 21 days before a meeting is held where it would be confirmed. The chairperson can also stand down on their own accord at anytime.
