Spanish & Portuguese
Spanish and Portuguese are both Iberian Romance languages that developed on the Iberian Peninsula, an area consisting primarily of present-day Spain, Portugal and Andorra.
Latin was introduced to Iberia in 210 BCE when ancient Rome invaded the peninsula. As the Iberians adopted Latin, the language absorbed influences from their indigenous languages such as Celtiberian and Basque. Over time, the spoken language developed into a "Vulgar Latin" that followed the basic models of Latin but borrowed words from the other languages. Even after the Visigoth invasions started during the 400s, Latin remained the official language of government and culture. However, the Germanic migrations broke the linguistic uniformity of Iberia. Along the west coast in Lusitania—the area that would become Portugal—the spoken dialect adopted many new words used by the Germanic tribes.
Beginning in 711 when Moors from Northern Africa conquered the region, Arabic became the official language of the peninsula. During the succeeding centuries, however, Christian kingdoms to the north gradually reclaimed Moorish Spain, taking the country back linguistically as well as politically, militarily and culturally. As the Christians moved South, their dialects became dominant. One in particular that originated in central-northern Iberia during the 9th century gradually spread into Southern and Eastern regions. This dialect—Castilian—gathered a sizable lexical influence from Arabic, especially in the later Medieval period.
A victory over the Moors in 1139 is traditionally regarded as when the independent Kingdom of Portugal was formed. By the time the Moors were completely expelled in 1249, that region's dialect had become the Portuguese language.
The creation of a standardized Spanish language based on the Castilian dialect began in the 1200s under King Alfonso X. Scholars in his court wrote original works and translated histories, chronicles and scientific, legal and literary works from Latin, Greek and Arabic. Indeed, this translation effort was a major vehicle for the dissemination of knowledge through Western Europe that laid the groundwork for the Renaissance.