 Guadalajara was founded on 14 February 1542 by Cristóbal de Oñate, a Basque conquistador, as the capital of the Kingdom of Nueva Galicia, part of the Viceroyalty of New Spain.After 1572, the Royal Audiencia of Guadalajara, previously subordinate to Mexico City, became the only authority in New Spain with autonomy over Nueva Galicia, owing to rapidly growing wealth in the kingdom following the discovery of silver.By the 18th century, Guadalajara had taken its place as Mexico's second largest city, following mass colonial migrations in the 1720s and 1760s.