The Jews of course were only the people of their own declared god YHWH, who in turn was borrowed from the Phoenecian pantheon of gods, YHWH being a son of the God El. So the Jews chose their own god to represent them and then claimed themselves to be "his people", or "God's chosen people", just like JWs do today.
There is of course no evidence for YHWH choosing anyone or ever having spoken or done anything at all-- but this is the very nature of religious belief.
So what is "pagan"? The word pagan originally referred to things from the countryside, and simply meant of the village, the word in Latin for village was pagus. Likewise the word heathen meant a dweller on the heath. In other words; relating to rustic life as opposed to educated civilisation found in cities. Fourth century Roman Christianity (when the Bible was compiled) saw itself as a civilised, sophisticated and urban (hence urbane) religion and wanted no demeaning connection with the peasantry.
The irony though is that the underpinning of Bible stories are indeed folk tales i.e. pagan, often based on almost universal mythologies drawn from very ancient fables about the sun, stars and constellations.