Trexenta is one of the richest agricultural districts of the island. Man's presence on the hillsides is evident in the high concentration of small villages dotted around. However, the area still preserves signs of the ancient communal organisation of the agricultural activities linked to extensive cereal cultivation. The region was inhabited in prehistoric times, but it was during the Carthaginian and especially Roman period that it experienced intense colonial exploitation, connected to the constitution of great estates. During the Middle Ages it became part of the Cagliari and Arborea district and fell under the dominion of the Council of Pisa. It was then incorporated in the Aragonese kingdom under the King of Spain, and became part of the Marquisate of Villasor in 1537.

The territory of Trexenta is composed of various localities, such as:
• Barrali
• Gesico
• Goni
• Guamaggiore
• Guasila
• Mandas
• Ortacesus
• Pimentel
• Sant'Andrea Frius
• San Basilio
• Selegas
• Senorbì
• Siurgus Donigala
• Suelli