The Diocese or Archdiocese of Mérida (dioecesis Emeritensis) was a Catholic and Arian see centred on the Spanish city of Mérida during the periods of Roman and Visigothic rule. Mérida was also the provincial capital of Lusitania.
The see prospered in the late fifth century under Zeno, a Greek, who was offered greater authority in order to defend the province from Suevic raids. At about that time the diocese fell under the control of the Visigoths and it remained a Visigothic see until the Moorish conquest of 711. Throughout that period, however, it only ever had two Gothic bishops: Masona and his successor Renovatus in the late sixth and early seventh centuries. In the mid-sixth century the see became the richest in Spain through the private wealth of bishops Paul and Fidelis, Greek uncle and nephew. Under these four, the city was ruled de facto by the bishops independent of the central government, a situation which led to conflict between the Arian king Leovigild and his bishop, Sunna.
The bishopric of Badajoz was erected in 1225, shortly after it was reconquered from the Moors by King Alfonso IX of Leon. Its first bishop was Don Pedro Perez, appointed by Alfonso X, the Wise. The diocese was suffragan to the archdiocese of Seville, and was bounded on the north by the diocese of Coria, diocese of Plasencia, and diocese of Toledo, on the east by Toledo, the diocese of Ciudad Real, and diocese of Cordoba, on the south by the archdiocese of Seville, and on the west by Portugal.