Joseph Manuel Montoya was born on September 24, 1915, in Peña Blanca, New Mexico, into a family of Roman Catholic descendants from eighteenth-century Spanish settlers. He received his early education in public schools in Sandoval County and graduated from Bernalillo High School before attending Regis College in Denver, Colorado.

He began his law studies at Georgetown University in Washington, D.C., where at age 21, while still a student, he became the youngest person in New Mexico’s history to be elected to the state House of Representatives.

After graduating from law school in 1938, he was re-elected and quickly rose to leadership positions, becoming majority floor leader. By 1940, he was elected to the New Mexico Senate as the youngest member ever, where he served multiple terms and held posts such as majority whip and chairman of the Judiciary Committee.

Between 1947 and 1957, he served three terms as Lieutenant Governor of New Mexico while also serving stints in the state senate.

In 1957, Joseph Manuel Montoya was elected to the U.S. House of Representatives in a special election and went on to serve four consecutive terms. As a Congressman, he was known for his moderate political stance, dedication to social programs, and focus on bringing federal aid to New Mexico, particularly for agriculture, education, urban housing, and the economically disadvantaged.

In Congress, he sponsored important legislation such as the Vocational Education Act and was a strong advocate for environmental conservation, sponsoring the Wilderness Act. In 1964, he was elected to the U.S. Senate to fill the seat of the late Senator Dennis Chavez and served there until 1977.

During his Senate tenure, he was a member of influential committees including Appropriations, Public Works, the Joint Committee on Atomic Energy, and the Senate Watergate Committee. Montoya was a proponent of worker and farmer rights, consumer protections, equal rights, and gun control. 

Despite his accomplishments, he faced controversies toward the later years of his career, including frequent late tax filings and investigations into campaign finance irregularities and real estate dealings, though he was never convicted of wrongdoing.

These issues likely contributed to his defeat in the 1976 Senate election by Republican Harrison Schmitt. After leaving office, he was implicated in the Koreagate scandal for receiving unregistered foreign campaign contributions.

He died from liver and kidney failure on June 5, 1978, in Washington, D.C.