Caltanissetta's origins can be traced back to 406 BC, when admiral Nicia of Hamilcar's siege force from Carthage established a fort at the site, later called Castra Nicia (Fort Nicia).
After the Second Punic War, Castra Nicia came under Roman rule, but as in the rest of Sicily, the influence of the invaders remained superficial.
In AD 829, the city was occupied by the Saracens. The similarity of the Carthaginian name to the Arabic word Nissa (meaning "women") resulted in the Saracen name of Qalat al Nissa ("Fort of the Women"), which has since been Italianized to Caltanissetta. The settlement was captured by the Normans in 1086. A charter was granted to the town in accordance with count Roger Borsa's vast plan for the urbanisation of Sicily and the urban plan that is still in evidence today was laid out.
After the Normans the city was under the Hohenstaufen, the Anjou and the Catalan-Aragonese kings, who gave it the title of county. Here Frederick II of Sicily was proclaimed king. The city was the seat of another Parliament who aimed to set the disputes arisen during the reign of Frederick III (1355–1377).
In 1406 Caltanissetta became a fief of the noble Spanish family Moncada, which already owned the estate of Paternò, and subsequently decayed deeply. In 1539 the construction of the Cathedral was started and in 1566 a notable bridge was built over the Salso River. In this period the city began to expand outside the walls, and new quarters (Santa Flavia, San Rocco degli Zingari and San Francesco, which included the medieval village of Arab origin) were created. The quartiers were divided by the construction of two roads that crossed roughly perpendicular to a central square (now Piazza Garibaldi): the Corso Vittorio Emanuele current (west-east) and the current Corso Umberto I (north-south)
On July 8, 1718 the city was assaulted by Piemontese troops, which caused large losses in the population. In 1787 Johann Wolfgang Goethe
