Chilean painter, founding member of Montparnasse Group and husband of painter Ana Enriqueta Petit also Marfan (better known as Henriette Petit). After a brief stint in law school at the University of Chile in 1915, he decided to devote himself to painting and enroll in free courses at the School of Fine Arts. His teachers were Juan Francisco Gonzalez, Pedro Luna and Jose Caracci who strengthened him independent pictorial desire and motivated him to travel to Europe. At that time, he was painting cityscapes in Santiago and Valparaiso, executed Impressionist manner. In 1919, the artist began a tour of Italy, Germany and France, countries where he attended free schools as the Hoffman Academy in Munich. In several of his trips he had the company of painter Camilo Mori. The most decisive was his stay in the French capital during the height of the great masters of the School of Paris. Vargas Rosas met there Picasso, Leger and Chirico, and educated at the Grand Chaumiere and Colarossi academies. The lack of means brought him back to Chile in 1923. He came willing to put in work creative projects and innovative ideas, but faced a reluctant to changes and conservative art scene. In Chile, the Spanish artist Fernando Alvarez de Sotomayor had imposed a rigid formal education stressing the realistic and narrative painting. Vargas Rosas took the initiative to found the Free Academy of Montparnasse, with his painter friends, Henriette Petit, José Perotti and July and Manuel Ortiz de Zárate brothers, all committed to providing the Chilean art following a different aesthetic line oriented, abstraction and in clear agreement with the French avant-garde. Supporters and opponents of the group gathered in 1925 in the historic Hall of June, Prime Free Art Hall, where still lifes and nudes were exposed were given. It was an event that despite the uproar provoked marked the starting point of the profound changes experienced by the Chilean plastic. The set of those who participated in the lounge, would be later known as Montparnasse Group. Rosas Vargas returned to Paris the same year, where two years later, he married Henriette, who would be his companion for the more rewarding period of his life. He studied engraving at Atelier Seventeen of Bill Hayter and became interested in the work of cubist Juan Gris. Marriage should definitely return to Chile in early 1939 to World War II. In 1946 he was appointed Director of the National Museum of Fine Arts, a post he held until 1970. During his tenure he raised the discussion on the role of the museum as a conservation center as art gallery.
He died in Santiago on 6 September 1977.