The town was abandoned after earthquakes in the 13th century; today the area is administered as a frazione of the comune of Manfredonia, in the province of Foggia.

According to legend, Sipontum was founded by Diomedes, product of the union of the Homeric hero of the same name with the daughter of the king of the Daunians.

In 189 BC it became a Roman colony with its original Sipious name still used in Byzantine times, and in 663 AD it was taken and destroyed by the Slavs.

Apparently, Tomislav sent the Croatian navy under Michael's leadership to drive the Saracens from that part of southern Italy and free the city.

[2] Before the second half of the 12th century, the Knight Templar and the Hospitalier Order founded their first Italian fincas in the area of Capitanata, which spanned from Siponto to Foggia, including Spinazzola,[3] Borgonioni, Salpi, Trinitapoli, Santa Maria de Salinis, Belmonte, Lama and Bersentino.

They were devoted to animal husbandry, the commerce of marine salt, the depot of dietary goods, the olive and vineyard cultivation, as well to the use of natural waterfalls through mills.

Such a skilful administration of their assets, grew the economic and military potential of the Orders, who were engaged in the Crusades and in the protection of local communities.

Archbishop Johannes of Trani, in his tomb inscription claimed to be "Archiepiscopus Tranensis, Sipontinensis, Garganensis Ecclesiae, atque Imperialis Synkellus.