The capitol of the independent northern kingdom of Israel founded ca. 870 BCE by the Ephraimite ruler Omri on a mountain ridge 12 miles northwest of Shechem on the central route from Jerusalem to Galilee. For more than 800 years it was known as Samaria and the territory it controlled was eventually named for it. The city was captured by Sargon II of Assyria [722 BCE], who deported 27,000 inhabitants and replaced them with captives from five Babylonian cities. Given its strategic location the city served as the provincial capital of the region for 600 years under Assyrian, Babylonian, Persian, and Hellenistic empires.
It was made subject to Jerusalem after a year long siege by Johanan Hyrcanus [ca. 110 BCE] who destroyed its fortifications. After Roman occupation, the walls were restored by Gabinius. The city sided with Herod against the Hasmonean prince Antigonus, who controlled Jerusalem [38 BCE]. Thus, Herod made it part of his building campaign, enlarging it and rededicating it to the emperor Augustus [Sebastos in Greek]. Remains of the large [230' x 280'] Herodian temple to Augustus with part of a marble statue of the emperor were uncovered in the modern excavations. According to Acts 8, this thoroughly Romanized city was the center of the first successful expansion of the Jesus movement among non-Jews.
As a monument to Roman domination, Sebaste was captured and burned by Jews early in their war with Rome [66 CE]. Though Roman forces under Vespasian recaptured it [69 CE], it was not restored until the end of the 2nd c. CE. Later Byzantine tradition claimed it was the site of the burial of Johanan the Baptizer.
Source: Into His Own