jingoyoudaoicibaDictYouDict[jingo 词源字典]
jingo: [17] The exclamation by jingo! has been around since at least the late 17th century, and the element jingo probably originated as a euphemistic alteration of Jesus. But it took on a new lease of life in 1878 when G W Hunt incorporated it into a music-hall song he was writing in support of Disraeli’s hawkish foreign policy towards the Russians. Its refrain went ‘We don’t want to fight, yet by Jingo! if we do, We’ve got the ships, we’ve got the men, and got the money too’. By jingo! was taken up as a nationalistic rallying call: those who supported Disraeli’s plan to send in the fleet were called jingoes, and their attitude was dubbed jingoism.

But these were terms used by their opponents, not by the jingoes themselves, and they were essentially derogatory, and when jingoism later broadened out in meaning, it denoted a mindless gung-ho patriotism.

[jingo etymology, jingo origin, 英语词源]
jingo (n.)youdaoicibaDictYouDict
"mindless, gung-ho patriot," 1878, picked up from the refrain of a music hall song written by G.W. Hunt, and sung by "Gilbert H. MacDermott" (1845-1901), supporting aggressive British policy toward Russia at a time of international tension. ("We don't want to fight, But by Jingo! if we do, We've got the ships, we've got the men, We've got the money too.")
Hunt's patriotic song of 1878, with a swinging tune ... became at Macdermott's instigation the watchword of the popular supporters of England's bellicose policy. The "Daily News" on 11 March 1878 first dubbed the latter 'Jingoes' in derision .... ["Dictionary of National Biography," London, 1912]
As an asseveration, it was in colloquial use since 1690s, and is apparently yet another euphemism for Jesus, influenced by conjurer's gibberish presto-jingo (1660s). The frequent suggestion that it somehow derives from Basque Jinko "god" is "not impossible," but "as yet unsupported by evidence" [OED].