Iglesias (, ; from ; ) is a comune and city in the province of South Sardinia, Italy. It was co-capital of the province of Carbonia-Iglesias with Carbonia, and the province's second-largest community. Under Spanish control Iglesias was one of the most important royal cities on Sardinia, and it is the seat of the Roman Catholic Diocese of Iglesias. At an elevation of in the hills of southwestern Sardinia, it was the centre of a mining district from which lead, zinc, and silver were extracted. Iglesias was also a centre for the distillation of sulfuric acid. History Prehistory and ancient history The area around present-day Iglesias was inhabited in prehistory, with the oldest traces of human settlement dating to the Neolithic. The fourth-millennium-BC domus de Janas, attributed to the Ozieri culture, were discovered in the mountainous region of San Benedetto. Other pre-Nuragic finds attributed to the Monte Claro, Bell Beaker and Bonnanaro cultures were discovered in nearby caves, followed by evidence of a Nuragic, Punic and Roman presence. Ancient Roman sources record a city known as Metalla, perhaps located along Iglesias' border with Fluminimaggiore. Medieval history During the ninth century AD, after a period of human absence, a small town arose with a Byzantine church (the Church of San Salvatore). When the Byzantine influence left Sardinia, the southern part of the island was controlled by the Judicate of Cagliari. After the fall of the Judicate in 1258, south-western Sardinia (the curatorias of Cixerri and Sulcis) was assigned to the Della Gherardesca family; the Cixerri region was controlled by Ugolino della Gherardesca. The count took advantage of the region's silver resources and established a city: Latin: Villa Ecclesiae (Churchville), renovating old buildings and constructing new ones. The Della Gherardesca family built the medieval Castle of Salvaterra, defence walls, a hospital and an aqueduct. After Ugolino's March 1289 death in Pisa's Tower of Muda (where he was imprisoned in the summer of 1288 for sedition and treason), his Sardinian holdings in the Cixerri reason were inherited by his son, Guelfo della Gherardesca; escaped from Pisa in 1288, he had settled in the Villa di Chiesa. Guelfo, hostile to the Pisan government, tried to seize one-sixth of the former Judicate of Cagliari (Sulcis) owned by Gherardo della Gherardesca's heirs and occupied Villamassargia's Castle of Gioiosa Guardia. Pisa's response was swift; in 1295 republican troops, supported by the forces of Marianus II of Arborea,