Omri in the Bible Encyclopedia - ISBE
            om'-ri (`omri; Septuagint Ambri; Assyrian "Chumri" and 
"Chumria"):
(1) The 6th king of Northern Israel, and founder of the 
IIIrd Dynasty which reigned for nearly 50 years. Omri 
reigned 12 years, circa 887-876 BC. The historical sources 
of his reign are contained in 1 Ki 16:15-28; 20:34, the 
Moabite Stone, Assyrian inscriptions, and in the published 
accounts of recent excavations in Samaria. In spite of the 
brief passage given to Omri in the Old Testament, he was one 
of the most important of the military kings of Northern 
Israel.
1. His Accession:
Omri is first mentioned as an officer in the army of Elah, 
which was engaged in the siege of the Philistine town of 
Gibbethon. While Omri was thus engaged, Zimri, another 
officer of Elah's army, conspired against the king, whom he 
assassinated in a drunken debauch, exterminating at the same 
time the remnant of the house of Baasha. The conspiracy 
evidently lacked the support of the people, for the report 
that Zimri had usurped the throne no sooner reached the army 
at Gibbethon, than the people proclaimed Omri, the more 
powerful military leader, king over Israel. Omri lost not a 
moment, but leaving Gibbethon in the hands of the 
Philistines, he marched to Tirzah, which he besieged and 
captured, while Zimri perished in the flames of the palace 
to which he had set fire with his own hands (1 Ki 16:18). 
Omri, however, had still another opponent in Tibni the son 
of Ginath, who laid claim to the throne and who was 
supported in his claims by his brother Joram (1 Ki 16:22 
Septuagint) and by a large number of the people. Civil war-
followed this rivalry for the throne, which seems to have 
lasted for a period of four years (compare 1 Ki 16:15, with 
16:23 and 29) before Omri gained full control...
                          
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