Having fled Indonesian-rule in his homeland, Mr Ayamiseba became a central figure in advancing the West Papuan independence cause in regional fora.
Based in Vanuatu's capital Port Vila, he was instrumental in establishing the West Papua National Coalition for Liberation which became an effective regional lobbying group.
It was the forerunner of the United Liberation Movement for West Papua which Mr Ayamiseba and others established to elevate their independence cause internationally.
The ULMWP brought together all the main pro-independence Papuan groups under one umbrella and in 2015 succeeded in gaining observer status at the Melanesian Spearhead Group.
With Mr Ayamiseba's help, the ULMWP established an office in Port Vila and worked with Vanuatu's government to express opposition to Indonesia's control of the Papua region.
Mr Ayamiseba was also a musician of significant renown, having toured Vanuatu in the 1980s as a founding member of the Black Brothers, the Papuan band whose members sought refuge there.
The Black Brothers went on to became a successful touring act throughout the Pacific Islands region.
The ULMWP's chairman, Benny Wenda, has paid tribute to Mr Ayamiseba, saying his death was a great loss for West Papuans.
"Andy stood for the dream of a West Papua free from Indonesian colonialism, a dream all West Papuan people share.
"The people of West Papua will always remember the courage, spirit and leadership of Andy Ayamiseba and his historic contribution to our struggle for freedom," Mr Wenda said.
The ULMWP head said the organisation would honour and respect Mr Ayamiseba's legacy in the Pacific region by continuing the Papuan struggle "to its victory".