Revelation 17:12-14 (KJV)
12 And the ten horns which thou sawest are ten kings, which have received no kingdom as yet; but receive power as kings one hour with the beast.
13 These have one mind, and shall give their power and strength unto the beast.
14 These shall make war with the Lamb, and the Lamb shall overcome them: for he is Lord of lords, and King of kings: and they that are with him are called, and chosen, and faithful.
Those on Jesus's side are His chosen people. For they have been called and have listened, in all faithfulness to their God.