Tidal was the king of 'Goiim' ('nations' or 'peoples') who joined the coalition of four kings against five in Genesis 14 — the first recorded military conflict in Scripture. He joined Chedorlaomer of Elam, Amraphel of Shinar (often identified with Babylon), and Arioch of Ellasar. This coalition defeated the five cities of the plain (including Sodom) and took Lot captive, prompting Abram's rescue mission.
The episode in Genesis 14 — involving Tidal and his coalition — is theologically significant for several reasons. It introduces the theme of Abraham as warrior-protector of his kin, foreshadowing the later military campaigns of Israel. Most significantly, Abram's victory over the four kings (including Tidal) is followed immediately by his encounter with Melchizedek, priest-king of Salem — a Christological type (Hebrews 7:1-3). The theological message: when God's chosen one goes to rescue the captive, he returns to worship and to receive blessing from the eternal priest. Tidal, 'king of nations,' is defeated by a man whose blessing comes from the Most High God, possessor of heaven and earth.