Joseph Manuel Montoya was born José Manuel Montoya on September 24, 1915, in Peña Blanca, New Mexico. He was the son of Thomas O. Montoya and Frances de La. His father, after mining gold in Arizona, returned to New Mexico to become sheriff of Sandoval County. Although his family was not wealthy, it was influential. Both parents traced their ancestry to seventeenth-century Hispanic roots. This was significant in New Mexico, where Hispanics in the northern part of the state proudly claimed unbroken descent from Spanish settlers, in contrast to those who came across the Mexican border as late as the twentieth century and who generally had a mixed Spanish-Indian genealogy.