Guas was lifelong member of the Liberal Party of Cuba, in 1925 was the youngest elected person to the Cuban House of Representatives, which he presided from April 1927 to August 1933.
[1] Guas went into exile, with his father and brother Gregorio (a dentist and also member of the Cuban House of Representatives) after President Gerardo Machado was overthrown in August 1933.
Guas was elected Mayor of Havana in November 1958, but did not assume the post after Castro seized power on January 1, 1959.
Guas sought asylum in the Chilean Embassy in Havana and returned to exile with his wife, Luisa Maria Decall and children, Hilda, Luisa, and Carlos Rafael Guas Decall (an attorney and member of the Cuban House of Representatives).
He tried to join the Brigade 2506 prior to the April 1961 Central Intelligence Agency-sponsored Bay of Pigs invasion but was rejected because of his age.