Having fallen into decay after the Gothic War it was conquered by the Longobards, becoming part of the Lombard Duchy of Benevento as seat of a gastaldry (district).

The city was destroyed in the years 847 and 860, by the Saracens, and again in the 11th century, during the war between King Roger II of Sicily and the Norman counts of the southern Italian mainland.

Its former cathedral cattedrale Santa Croce, dedicated to the Holy Cross, now in ruins, was decommissioned after the bishops transferred their see to nearby Cerreto Sannita, yet the see retained the alternative title Diocese of Telese as well, even after a further merger into the Diocese of Cerreto Sannita–Telese–Sant’Agata de’ Goti.

It possesses remains of walls in opus reticulatum, of a total length of over a mile; two inscriptions of the Republican period record the erection of towers.

The remains of baths (Thermae Sabinianae) and of an amphitheatre still exist; the city was supplied with water by an aqueduct.