Dennis Chávez (christened "Dionicio") was born in Los Chávez, Valencia County, New Mexico on April 8, 1888. His parents, David and Paz (Sanchez) Chávez were members of families that had lived in Los Chávez for generations. In 1895, David Chávez moved his family to the Barelas section of Albuquerque where Dennis attended school until financial hardships necessitated that he go to work. His first job was delivering groceries at the Highland Grocery store. Later on, he studied engineering and surveying at night and worked as an engineer for the City of Albuquerque for several years.
In 1911, Chávez married Imelda Espinosa, a member of a prominent New Mexico family. In 1914, they moved to Belen. He worked briefly as editor of a Belen weekly newspaper, as a court interpreter, and as a private contractor until 1916, when he obtained temporary employment as a Spanish interpreter for Senator A. A. Jones' reelection campaign. In 1918, he was offered a position as assistant executive clerk of the Senate in Washington, D.C. by Senator Jones. He accepted this position, passed a special admission exam at Georgetown University Law School and studied law at night. He graduated from Georgetown in 1920 and returned to Albuquerque to establish a law practice.
In 1922, Chávez ran successfully for the New Mexico state legislature. In 1930, he was elected as the Democratic candidate to the U. S. House of Representatives; in 1932, he became chairman of the Committee on Indian Affairs. Chávez was defeated by Bronson Cutting for a Senate seat in 1934, but when Cutting was killed in 1935, Governor Clyde Tingley appointed Chávez to fill the vacant seat. He was elected to serve out the remainder of the unexpired term in 1936, and was re-elected in 1940, 1946, 1952, and 1958.
Chávez was instrumental in improving higher educational facilities in New Mexico. He actively supported legislation to benefit farmers and protect New Mexico's share of water from the Colorado River. Chávez was pro-labor, co-sponsoring the Fair Employment Practices Commission Bill; he was involved with legislation pertaining to Indian affairs; he was an advocate of the Good Neighbor Policy toward Latin America. Dennis Chávez was chairman of the Committee on Post Office and Post Roads, the Committee on Public Works, and the Senate Subcommittee for Defense Appropriations. Chávez was the first native-born Hispanic elected to the U. S. Senate. At the time of his death, he was fourth ranking in Senate seniority. He died in Washington D. C. on November 18, 1962 and is buried at Mount Calvary Cemetery in Albuquerque.