Long ago, this site was occupied by the Celts, but the process of Romanisation brought a great cultural transformation to this region. The presence of the Romans is still visible in the various archaeological remains housed at the Museu Nacional Machado de Castro, built over the cryptoporticus of the Civita Aeminium, the forum of the Roman city. After them, between 586 and 640, came the Visigoths, who altered the name of the town to Emínio. In 711, it became a Moorish and Mozarab city. In 1064, the city was conquered by the Christian Fernando I of Castile and governed by the Mozarab Sesnando.