This is the most important subject, & takes up most of the bible, in many ways is also linked to our time too. God's chosen nation of Israel were always worshipping other mythical gods, & making their own, like the golden calf etc, that also included lecherous practices. There was only a remnant of Israel that remained relatively faithful to God.
God told Israel time & time again, that if they go after other gods He will send the sword, famine & pestilence, over & over, & then in Lev26v25 He said they will be delivered into the hand of the enemy (the beast-Babylon).
The other problem Israel faced is not keeping the sabbath of years, in which every 7th year they had to let the land lie fallow (much like farmers do, to allow the nutrients of the earth to flourish again) & under the reign of kings, being around 510 years, for 490 of those years, they didn't keep the sabbath, which then forms the 70 x 7 weeks of years of Daniel. When Judah was carried off into captivity in 586BC, Jerusalem's laid waste, & couldn't be built on for 70yrs, to make up for the 70 times they didn't keep the 7th year sabbath. Of course, that meant Israel did not have a temple to worship in, & so they had to compromise by starting synagogues, & their compromised scriptures, forming the Halakah, which could be written But not read, & the Hagadah, which could be orally spoken, but not written. They believed through the rabbis, that this took precedence over Moses law.
The start of the 70 weeks of Daniel came in Neh2v1 around 445BC, when Nehemiah got an edict to build the walls of Jerusalem. 483 of 490yrs takes us to Yeshuah coming on the colt of an ass, & wept over Jerusalem, & declared that the gospel was now hidden from the Jews, Luke19v42 & then the gentiles will be spiritual Israel (gentile elect church), or should I say a remnant of them, much like in the OT for Israel.
Daniel's 70th week, years 484-490, we await, before Yeshuah comes at the last trump, & declares time is no more, & into eternity with His elect church. No 1000yr reign after, as we have been in the millennium since Acts2, as the 1000yrs in Rev20 are chilia in Greek, & is plural, so at least 2000, it surely cannot be 3000!!