New papers on the Hobbit dispute reveal the Government came under intense pressure to do a deal to ensure that the films were made in New Zealand.
The papers - finally released on Tuesday under the Official Information Act after appeals by Radio New Zealand and the Council of Trade Unions - also confirm that a union blacklist on the movies was lifted about 18 October 2010, even though government ministers denied it at the time.
Despite the lifting of the blacklist, the papers show that Hollywood studios and Hobbit director Sir Peter Jackson continued to push the Government to change employment law.
The documents show that the Government was initially reluctant to change the law to meet the concerns of US company Warner Bros.
On 4 October 2010, government ministers wrote to Sir Peter before the union blacklist was lifted, saying there was no need to change it.
The New Zealand director and his partner Fran Walsh wrote back, saying that the Government needed to change the law to make it clear that actors and crew were contractors - not employees.
The couple said they were very concerned that Hollywood studios no longer viewed New Zealand as a safe place to make films.
Later that month, the Government bowed to the studios' demands and changed the law under urgency in the House in a day to make it absolutely clear that actors and crew were independent contractors.
The documents also reveal the level of Sir Peter's personal animosity towards union official Simon Whipp. In one email, Sir Peter refers to Mr Whipp as "a snake" and says: "He is in revenge mode, intent on inflicting as much damage as he can to our film, to our film industry, to our country."
Phil Darkins, an organiser for the union Actors Equity NZ, told Radio New Zealand's Checkpoint programme on Tuesday the documents make it clear that industrial disputes were not behind the uncertainty about whether the films would be made in New Zealand.
"Any claim that the dispute was the main cause of any asserted uncertainty over The Hobbit has been proven to be incorrect once more as Peter Jackson stated in an email to the Government.
"There is no connection between the blacklist and its eventual retraction and the choice of production base for The Hobbit."
Union wants to know why Govt changed mind
Council of Trade Unions president Helen Kelly wants to know why the Government reversed its position and changed employment law in a day in response to the Hobbit dispute.
"There's a very important document which shows that their assessment was that there didn't need to be to get the films made here and provide security any change to either the Commerce Act of the Employment Relations Act."
Ms Kelly said the papers reveal Sir Peter Jackson and government ministers knew the union blacklisting of the Hobbit films was being lifted, even though at the time they denied it had.
However Gerry Brownlee, who was Economic Development Minister at the time, said on Tuesday that was never clear and scoffed at suggestions the CTU said nothing because it had been asked to keep quiet by Warner Bros.
"They're in a dispute with Warner Bros Studios and Warner Bros say, 'Please don't say the dispute's over and so they don't' - that's utterly ridiculous.
"Helen Kelly needs to get her story straight. They were very opposed to this production going ahead under the ... changed tax position that we were bringing in for the actors making them contractors. They didn't want this to go ahead."