What does Genesis 14:2 mean?

these kings joined forces and went to war against Bera, king of Sodom; Birsha, king of Gomorrah; Shinab, king of Admah; Shemeber, king of Zeboiim; and the king of Bela (also called Zoar). Genesis 14:2 - Modern Text Bible

(Five local kings, including Sodom and Gomorrah, are attacked by the four foreign kings.)