A legendary Australian gay rights campaigner who died last month has been awarded a rare posthumous honour.

Lex Watson founded the Campaign Against Moral Persecution in the 1970, the first gay rights group in Australia, and was later the president of the AIDS council of New South Wales.

He passed away last month aged 71 following a long battle with cancer, but today was made a member of the Order of Australia in the Queen’s birthday honours list.

The Order of the Australia is the equivalent to a British Knighthood, and like British honours it is not usually granted after death.

However, nominations made while people are still alive can still be considered if they die in the meantime.

At the time of his death, Watson was the president of the Pride History Group.

In a statement they wrote: “For many of his generation and beyond, Lex Watson was the face of gay activism in Sydney.

“He was a foundation member of the Campaign Against Moral Persecution (CAMP), the organiser of the first gay rights demonstration in Australia, a passionate advocate of homosexual law reform and anti-discrimination legislation, an AIDS activist, and a keen advocate for the preservation of gay community history.

“His was a courageous life of towering achievement.

“After retirement, Lex became involved in the Pride History Group. He was president at the time that he died on May 6, 2014, assisting in the organisation of a November history conference on homosexual law reforms, his major life’s work.

“The conference will be dedicated to his memory.

“Lex is survived by his sister, brother-in-law and two nephews and their families.

“He is remembered with respect and affection by his fellow academics, and admired by his fellow activists for his monumental achievements.”

The Queen’s Birthday Honours list in the UK will not be announced until June 14.