The former chief executive of Creative Scotland, the national arts funding body, believed a letter of protest signed by more than 100 artists last year was a "highly political" act by people opposed to its existence.

In the combative email from Andrew Dixon to chairman Sir Sandy Crombie, Mr Dixon said the devastating letter of protest, signed by artists and writers such as John Byrne, Don Paterson, James Kelman and the nation's Makar Liz Lochhead, was just the latest in a series of such attacks by artists "fundamentally opposed" to the existence of Creative Scotland.

The email is part of a cache of documents provided to The Herald under Freedom of Information legislation. The material covers the last six months of 2012, when the funding body was caught in public crisis not seen before in the Scottish cultural scene. Creative Scotland has since acknowledged many deficiencies in its policies and approach, and is in the process of reform.

However, Mr Dixon's email reveals his view that the October 8 letter, since widely acknowledged as a genuine series of concerns, was an antagonistic attack on the body by artists who had already signalled their dislike of it.

But, last night, Kenneth Fowler, head of communications for the body, which distributes £80 million a year in government and Lottery funds, said it does not believe the artists' letter was a political act and has "recognised the real concerns raised".

The funding body is holding public meetings with artists, has unveiled a new series of funding pots and next week will interview for a new chief executive.

In the email, titled History, written at 7am on October 9 last year, Mr Dixon says he had been warned the arts community could be "back biting". He writes: "Sandy – I thought this might be of interest – Yesterday's letter to you, if indeed it ever did get sent to you, follows in a line of such letters dating back to 2008.

"I was warned in the press on my appointment of 'back biting' arts community and a previous 'loss of trust' through the birth of Creative Scotland but what you can see here, and will get from Ewan Brown [former chairman of Creative Scotland's transition board] is the history of over 400 artists, many of them on the list yesterday who fundamentally opposed the creation of Creative Scotland. This was highly political."

The email, insiders say, displays Mr Dixon's feelings in an emotional moment, but also his view that there was a degree of antagonism between artists and the very idea of Creative Scotland itself.

The letter signed by the artists led to public meetings, internal reviews by Creative Scotland's board, and to the departure of Mr Dixon and the body's senior director, Venu Dhupa.

Notably, in his resignation statement on December 3, Mr Dixon said: "I have been disappointed, given my track record, not to gain the respect and support of some of the more established voices in Scottish culture and I hope that my resignation will clear the way for a new phase of collaboration between artists and Creative Scotland."

The October 8 letter, ultimately signed by more than 400 online, attacked Creative Scotland's "ill-conceived decision-making, unclear language, lack of empathy and regard for Scottish culture". Leading arts figures said trust between artists and the funder was "low and receding daily".