Martinez de Irala, Domingo (c. 1509-56), Spanish conquistador.
Martinez de Irala went with Pedro de Mendoza to the New World in 1536 and helped found Buenos Aires.
He explored the La Plata, Paraguay and Parana river regions and founded Asuncion in 1537, moving the colony's administration there from Buenos Aires. He served as governor of the Spanish colonies from 1538 to 1540. Cabeza de Vaca was later appointed governor of the region, but Martinez de Irala revolted against his leadership, imprisoned him and then deported him to Spain. Martinez de Irala served as governor again from 1544 to 1548.