Originally an officer in the Spanish Army, Arista later joined the revolutionary army of Agustín de Iturbide. Later, Arista served with Antonio Lopez de Santa Anna, Mexico's on-again off-again dictator during the attempt to put down the 1836 rebellion in Texas.
In 1846, Arista was given command of the Army of the North and sent to expel American troops from what Mexico viewed as its legitimate territory in Texas. The resulting engagements ignited the bloody Mexican-American War of 1846-1848. Arista was in command of Mexican forces during the Battle of Palo Alto and the Battle of Resaca de la Palma.
Arista's military skills are subject to debate by those who study the conflict. While personally quite brave, Arista was a dedicated liberale - a member of Mexico's liberal faction, and therefore the natural enemy of his largely conservative general staff. At both the Battles of Palo Alto and Resaca de la Palma, Arista was ill served by the political division among his staff.
After Resaca de la Palma, Mexico's government recalled Arista and he was removed from command. Later absolved of guilt for the defeats at Palo Alto and Resaca de la Palma, Arista spent the rest of the war as a functionary, seeing little combat.
In 1851, Arista succeeded José Joaquín Herrera as president, and sought to bring fiscal stability to the nation. Conservative resistance to Arista's rule, and an eventual revolt by the saidsame conservatives lead to his resignation and exile in 1853.