Hastings' Dictionary of the Bible (1898)
HADADE'ZER, or HADARE'ZER (Hadad's help), a king of Zobah. He was twice defeated bv King David's armies. 2 Sam 8:3; 2 Sam 10:16. On the first occasion 20,000 of the enemy were slain and 1000 chariots were taken. Amongst the spoil were shields of gold, 1 Chr 18:7, which David took to Jerusalem. Some years afterward. Hadadezer and three other Syrian princes formed an alliance to assist the Ammonites against David; but the whole Syrian army was defeated on the east bank of the Jordan by the Israelites under the command of Joab.
Between 40,000 and 50,000 of the enemy were killed, including their principal general, and they thenceforth became tributary to David. 1 Chr 19:16-19.