Renaldo claimed in his defense that he was born in Camden, New Jersey, and only later raised in Romania as Basil Couyanos by people whom he sometimes referred to as "mother" and "father" but at other times by their Christian names, Demetri and Theodora.

In January 1933, Renaldo was sentenced to serve two years in federal prison and fined $2000 on conviction of falsely claiming American citizenship, falsifying a passport, and perjury, but he eventually was pardoned by President Franklin D. Roosevelt and returned to acting.

Renaldo did play some roles in mainstream films as well, including Spawn of the North (1938), with George Raft, Henry Fonda and John Barrymore, and For Whom the Bell Tolls with Gary Cooper and Ingrid Bergman.

[citation needed] In the late 1940s, Renaldo starred in several Hollywood westerns as The Cisco Kid, and in 1950, he began playing the role in a popular television series that ran until 1956.

Two of his large paintings of members of the Maasai tribe whom he met in Kenya while filming Trader Horn were prominently displayed in his Santa Barbara home in 1971.