Jose Marcos Peña was baptized on 8 May 1781, the son of Juan Jose Peña and Margarita Salinas.
He married Maria Eustaguia Garcia on 14 Jul 1805.
In 1782, he lived at Los Salinas. The church census recorded that he was a young child, español, and 1 years old. His household included 5 people:
Juan Jose Peña, español, married, age 41.
Margarita Salinas, española, married, age 25.
Pedro Jose Peña, español, a child, age 10.
Maria Petra Peña, española, a child, age 7.
Jose Marcos Peña, español, a young child, age 1.