“A chip on your shoulder” is believed to have originated at least back to the early 19th century when a boy would put a chip on his shoulder and dare another to knock it off. If the other boy knocked it off then they would usually enter into a fist fight.
The “Long Island Telegraph” newspaper on May 20, 1830 explained the phrase as follows: “When two churlish boys were determined to fight, a chip would be placed on the shoulder of one, and the other demanded to knock it off at his peril.”
Now days the expression no longer means to actually have a literal chip on one’s shoulder, but to always go around in the objective case and kickative mood.
Dub Mowery is a Gospel preacher in the Church of Christ. A native of Southeast Oklahoma, he is the author of Colloquial Sayings & Expressions (Morris Publishing, 2008)