The earliest known document in Galician-Portuguese dates from 1228. The Foro do bo burgo do Castro Caldelas was granted by Alfonso IX of León to the town of Burgo, in Castro Caldelas, after the model of the constitutions of the town of Allariz. A distinct Galician Literature emerged during the Middle Ages: In the 13th century important contributions were made to the romance canon in Galician-Portuguese, the most notable those by the troubadour Martín Codax, the priest Airas Nunes, King Denis of Portugal and King Alfonso X of Castile, Alfonso O Sabio ("Alfonso the Wise"), the same monarch who began the process of establishing the hegemony of Castilian. During this period, Galician-Portuguese was considered the language of love poetry in the Iberian Romance linguistic culture. The names and memories of Codax and other popular cultural figures are well preserved in modern Galicia and, despite the long period of Castilian linguistic domination, these names are again household words.

The earliest Galician-Portuguese documents date back to which year?