When did the first case of hijacking occur?
We assume you're wondering about airplanes. In that case, the more correct question is, "When was the first "skyjacking?"
Although used interchangeably today, the word "hijacking" hasn't always applied to airplanes. In fact, the term originated the 1920s and 30s in the U.S. when gangsters were seizing trucks or other vehicles from America's streets.
The first recorded skyjacking of an airplane took place on Feb. 21, 1931 at the city of Arequipa, Peru when a group of rebel soldiers in Peru forced two American pilots to fly them about and drop propaganda leaflets over Lima. The pilots refused and the rebels ended their seizure on March 2, without any damages to the plane.
The first case of skyjacking within the United States occurred on May 1, 1961, when a man forced a commercial airliner enroute from Miami to Key West, Fla., to detour to Cuba. It was the first of four flights diverted to Cuba that year.
—The Fact Monster