Renaldo Gillet Kuhler was born November 21, 1931, in Teaneck, New Jersey, son of Otto August Kuhler, a German-born industrial designer of streamlined trains, and Simonne Gillet Kuhler, a Belgian.

Raised in Rockland County, New York, Renaldo was a troubled child. His father was mostly absent, traveling extensively for work; his mother was often neglectful and cold. He was bullied and beaten at boarding schools, but it was there that he became fascinated with Russian history after seeing two films, The Rise of Catherine the Great and Knight Without Armor starring Marlene Dietrich.

In 1948, at age sixteen, he moved with his parents to a remote cattle ranch (the KZ Ranch) in the Colorado Rocky Mountains. To cope with the  ensuing isolation and boredom, Renaldo invented an imaginary country he called Rocaterrania and began illustrating the nation's history as it unfolded.

In 1953 Renaldo left the KZ Ranch for Denver, where he was unable to find steady employment. In 1954 he enrolled at the University of Colorado, where he was ridiculed and ostracized by classmates for being different. He befriended renowned experimental filmmaker Stan Brakhage in Boulder, and drafted the titles for Brakhage’s Dog Star Man in original ornate calligraphy.

When a college student, Renaldo began exploring many of the world's religions, including Protestant faiths, Catholicism, Hinduism, Buddhism, Islam, the Bahai Faith, and Judaism. He was not born Jewish, yet he became especially fascinated with Judaism, sympathized with the plight of Jews in Nazi Germany and with Eastern European Jews in general, studied Hebrew and Yiddish, and enjoyed Hebrew orthography.

In 1961, after graduating from the University of Colorado with a B.A. in History, he worked as a curator for the Eastern Washington State Historical Society in Spokane. In 1963 he legally changed his name from "Ronald Otto Louis" to "Renaldo Gillet" Kuhler.

In 1967 Renaldo returned to Boulder, where he completed a certificate program in museum techniques at his alma mater, the University of Colorado. In 1969 he was hired by the North Carolina Museum of Natural Sciences. He taught himself the craft of scientific illustration and created thousands of natural history drawings for publications and exhibits over a thirty-year career.

Unbeknownst to family, friends, and co-workers, Renaldo had continued in secrecy to illustrate the history of Rocaterrania, the imaginary country he had invented as a teenager.

Renaldo met filmmaker Brett Ingram in 1996, marking the beginning of a 17-year friendship. Kuhler considered Ingram the son he never had, and it was this kinship that prompted Renaldo to share his secret creation with Ingram before anyone else. Ingram soon realized that the history of Rocaterrania was no mere fantasyland; it was a coded, metaphoric account of Renaldo's life.

In 2009, an article by John Strausbaugh for The New York Times announced the release of Ingram's Rocaterrania, a 74-minute documentary film revealing Renaldo’s remarkable life story, the history of his imaginary country, and his astounding body of work to the world.

Kuhler's work was subsequently exhibited at the American Visionary Art Museum in Baltimore, Gregg Museum of Art & Design in Raleigh, and the Outsider Art Fair in New York. Renaldo's European premiere at Halle Saint Pierre in Paris opened a few months after his passing on June 2, 2013.