When Jesus returns he will defeat all the kings of the world who oppose him. His kingdom will rule justly using the laws of God. He will have all the newly resurrected Christian saints with him. Who will those saints be, and how did they become one?
Revelation 19:11-21 Jubilee Bible 2000
11 And I saw the heaven open, and behold a white horse; and he that was seated upon him was called Faithful and True, and in righteousness he judges and makes war. 12 And his eyes were as a flame of fire, and on his head were many crowns; and he had a name written, that no one has known, but he himself. 13 And he was clothed with a garment dipped in blood; and his name is called The Word of God. 14 And the armies that are in the heaven followed him upon white horses, clothed in fine linen, white and clean. 15 And out of his mouth goes a sharp sword, that with it he should smite the Gentiles; and he shall rule them with a rod of iron; and he treads the winepress of the fierceness and wrath of Almighty God. 16 And he has on his garment and on his thigh a name written, KING OF KINGS, AND LORD OF LORDS. 17 And I saw an angel standing in the sun; and he cried with a loud voice, saying to all the fowls that flew in the midst of the heaven, Come and gather yourselves together unto the supper of the great God, 18 that ye may eat flesh of kings and flesh of captains, and flesh of mighty men and flesh of horses and of those that sit on them and the flesh of everyone, free and bond, both small and great. 19 And I saw the beast and the kings of the earth and their armies gathered together to make war against him that was seated upon the horse and against his army. 20 And the beast was taken and with it the false prophet that wrought miracles in its presence, with which he had deceived those that had taken the mark of the beast and had worshipped its image. These two were cast alive into the lake of fire burning with brimstone. 21 And the others were slain with the sword that proceeded out of the mouth of him that was seated upon the horse; and all the fowls were filled with their flesh.
Revelation 20:4-6 New Life Version
4 Then I saw thrones. Those who were sitting there were given the power to judge. I saw the souls of those who had been killed because they told about Jesus and preached the Word of God. They had not worshiped the wild animal or his false god. They had not received his mark on their foreheads or hands. They lived again and were leaders along with Christ for 1,000 years. 5 The rest of the dead did not come to life again until the 1,000 years were finished. This is the first time many people are raised from the dead at the same time. 6 Those who are raised from the dead during this first time are happy and holy. The second death has no power over them. They will be religious leaders of God and of Christ. They will be leaders with Him for 1,000 years.