Galeno, who had joined POLOP in 1962, had served in the Army, participating in the uprising of sailors against the military coup, for which he had been arrested in Ilha das Cobras.
Galeno, que aderiu ao POLOP em 1962, tinha servido no Exército, participando na revolta dos marinheiros contra o golpe militar, pelo que tinha sido preso na Ilha das Cobras.