Aviz (ävēzhˈ) [key], village, Portalegre dist., central Portugal, in Alto Alentejo. The Castilian order of the Knights of Calatrava assisted in driving the Moors from Portugal and in 1166 settled at Évora. Alfonso II granted (1211) them Aviz, and this branch of the order became separate and was known as the Order of Aviz, a strictly Portuguese organization. The knights played an important part in Portuguese history. After the death of Ferdinand I in 1383, his illegitimate brother, John, who was master of the Order of Aviz, led a revolution to prevent the crown from going to Beatriz of Castile. He himself became king as John I. Thus the house of Aviz was established on the throne. It was the most distinguished of Portuguese dynasties, reigning until 1580, when Portugal passed for a time under Spanish rule (see Portugal). Aviz is sometimes spelled Avis.