The actor passed away at his home in Everdingen in the Netherlands on 3 January (12). Details of his death have only just emerged.
Martinez left Mexico for Los Angeles after making his breakthrough in the 1967 movie Pedro Paramo, and went on to work in film, TV and onstage for more than 30 years.
He starred in a number of Western TV shows, including Gunsmoke and Bonanza, and also appeared on Dynasty, L.A. Law and Ironside.
Martinez also appeared onstage with Christopher Reeve in Tennessee Williams' Summer and Smoke in 1988, as well as in the James Bond thriller Die Another Day in 2002.
The star is best remembered for his part in Sydney Pollack's Jeremiah Johnson and for playing the title role in Ulzana's Raid.