 Moreno was born in Buenos Aires in 1778 . His father was Manuel Moreno y Argumosa , born in Santander , Spain , who arrived in the city in 1776 and married María del Valle . Mariano was the firstborn of the Moreno family , and had thirteen brothers . During his youth he studied Latin , logic , and philosophy at San Carlos Royal College , followed by college studies of law at Chuquisaca . During these studies , he learned the new ideas of the Spanish Enlightenment . He married María Guadalupe Cuenca and returned to Buenos Aires , becoming a prominent lawyer for the Cabildo . Unlike most other criollos , he rejected the Carlotist project and the administration of Santiago de Liniers , joining instead the ill @-@ fated mutiny of Álzaga against him . He worked for the next viceroy , Baltasar Hidalgo de Cisneros . He wrote the economic paper The Representation of the Landowners , which persuaded the viceroy to open trade with Britain . 
