Born in Guadalajara, Mexico, Xavier Martinez was a painter noted for his Tonalist style, an etcher, lithographer and long-time art activist in northern California.

He began his art studies in Mexico, and moved to San Francisco in 1893 when his stepfather became consul-general from Mexico.  Martinez enrolled at the School of Design as a pupil of Arthur Mathews and won high honors including a scholarship to study with Jean Leon Gerome at the Ecole des Beaux-Arts in Paris where he stayed six years.  He also spent time with James McNeill Whistler, who had a strong influence on his work, especially with the Tonalist aesthetic..

In 1901, he established a studio in San Francisco and became one of the city's most colorful, popular Bohemian characters. Known as "Marty," he wore baggy velvet trousers, corduroy coat, colorful sash, crimson tie, and velvet beret.

With William Keith and Charles Rollo Peters, he co-founded in Monterey the Del Monte Art Gallery, which was the first gallery dedicated to California artists.  In 1906, his studio was destroyed by fire, and he moved across the bay to Piedmont where the surrounding hills became a frequent subject of his canvases.

From 1909 to 1942, he was Professor of Painting at the California College of Arts and Crafts in Oakland and was so revered the California legislature adjourned early as a gesture of respect the day he died.  A retrospective exhibition in 1974 in Oakland included many Southwest as well as California landscapes.