When was the first ever terrorist attack? That is, an attack that was classified as a ‘terrorist’ action?
The French revolution.
Not a single attack, I know, but that’s when the word originated. According to M-W, the first recorded use of the word “terrorist” was in 1795.
The word was originally a reference to the reign of terror of 1793-94. Very quickly, the term was used to brand anyone who seeked to achieved political goals through violence.
So, I don’t think you could trace it back to a single event. The term was also used to refer to brutal dictatorial policies of intimidation (like the reign of terror), so there has been some drift in meaning.
As soon as people were aware that fear could be used to influence people (i.e. pre-caveman days). It’s too open-ended to tie down unless you add some pretty big qualifiers to the question.
The first suicide car bombing took place here in America. It was commited by an anti-tax protester, and is known as the Bath School Disaster.
In addition, he blew up a school full of children.