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late Old English (c.1050), wyrre, werre, from Old North French werre "war" (Modern French guerre), from Frankish *werra, from Proto-Germanic *werso (cf. Old Saxon werran, Old High German werran, German verwirren "to confuse, perplex"). Cognates suggest the original sense was "to bring into confusion."
Spanish, Portuguese, and Italian guerra are from the same source; Romanic peoples turned to Germanic for a word to avoid Latin bellum because its form tended to merge with bello- "beautiful." There was no common Germanic word for "war" at the dawn of historical times. Old English had many poetic words for "war" (wig, guð, heaðo, hild, all common in personal names), but the usual one to translate Latin bellum was gewin "struggle, strife" (related to win).
First record of war time is late 14c. Warpath (1775) is originally in reference to North American Indians, as are war-whoop (1761), war-paint (1826), and war-dance (1757). War crime first attested 1906. War chest is attested from 1901; now usually figurative. War games translates German Kriegspiel (see kriegspiel).
"to make war on," mid-12c.; see war (n.). Related: Warred; warring.
The Israelites had to take possession of the Promised Land by conquest. They had to engage in a long and bloody war before the Canaanitish tribes were finally subdued. Except in the case of Jericho and Ai, the war did not become aggressive till after the death of Joshua. Till then the attack was always first made by the Canaanites. Now the measure of the iniquity of the Canaanites was full, and Israel was employed by God to sweep them away from off the face of the earth. In entering on this new stage of the war, the tribe of Judah, according to divine direction, took the lead. In the days of Saul and David the people of Israel engaged in many wars with the nations around, and after the division of the kingdom into two they often warred with each other. They had to defend themselves also against the inroads of the Egyptians, the Assyrians, and the Babylonians. The whole history of Israel from first to last presents but few periods of peace. The Christian life is represented as a warfare, and the Christian graces are also represented under the figure of pieces of armour (Eph. 6:11-17; 1 Thess. 5:8; 2 Tim. 2:3, 4). The final blessedness of believers is attained as the fruit of victory (Rev. 3:21).