'Kings of the Earth' in the Bible

and from Jesus Christ, the faithful and trustworthy Witness, the Firstborn of the dead, and the Ruler of the kings of the earth. To Him who [always] loves us and who [has once for all] freed us [or washed us] from our sins by His own blood (His sacrificial death)—

Then the kings of the earth and the great men and the military commanders and the wealthy and the strong and everyone, [whether] slave or free, hid themselves in the caves and among the rocks of the mountains;