Castile gave the world the Spanish language and claimed the Americas
The Crown of Castile began in 1230 as a union of two Iberian kingdoms. Within three centuries it had sponsored Columbus, absorbed the Aztec and Inca empires as Castilian possessions, and made its own dialect so dominant that the world now simply calls it Spanish.
León grew out of the old kingdom of Asturias, and Castile started as one of its counties before becoming a kingdom in the 11th century. The two were joined twice and split again before Ferdinand III made the union stick: he inherited Castile from his mother Berengaria in 1217 and León from his father Alfonso IX in 1230. He went on to conquer the Guadalquivir Valley, and his son Alfonso X took Murcia from Al-Andalus. Earlier, between 1199 and 1201, Castilian armies had seized western Navarre, including San Sebastián and Vitoria, though those Basque lands kept their charters.
The two parliaments merged almost at once, organised in three estates of nobles, clergy and towns, with John I eventually fixing which cities could send representatives. Local legal traditions survived, but a common body of law grew up through the Siete Partidas of about 1265, the Ordenamiento de Alcalá of 1348 and the Leyes de Toro of 1505, which stayed in force until Spain's civil code of 1889.
Language is Castile's most visible legacy. In the 13th century Castilian competed with Leonese, Basque and Galician-Portuguese, but under Alfonso X it became the official language of public documents, even replacing Latin for translations from Arabic. Scholars debate whether that reflected the language's own vigour or the influence of Hebrew-speaking intellectuals wary of the Church's Latin. In 1492 Antonio de Nebrija published the first grammar of Castilian, and conquistadors carried it across the Atlantic.
That same year Columbus's voyage opened the Americas, and in 1506 the overseas territories became kingdoms of Castile's heirs. Conquests of the Aztec and Inca empires, New Granada and the Philippines swelled its reach. Castile survived the 1479 union with Aragon through the marriage of the Catholic Monarchs, and Habsburg kings such as Charles I kept the title. Only after Philip V won the War of the Spanish Succession did his Nueva Planta decrees of 1716 fold both crowns into what everyone called Spain.
Source: Crown of Castile
