As today: motivated by money

Here's another alternative memory which seems to jump out to people suddenly, and hence is being called a Mandela Effect.

When you hear the terms "hack" and "telecoms network" you picture up shadowy figures in a darkened room, hunched over keyboards in front of computer screens with lots of flashy lights. In fact, this represents just the modern version of a system designed in the 1790's, which used a series of mechanical arms on towers placed on hills to communicate. Both are intended to transfer messages further than a single person could see, as quickly as possible, using the technology of the day.

However, a system did indeed exist - and was used to communicate stock prices. One of the operators in the chain was bribed to send fake data, which allowed the bad guys to profit since they were the only ones with the real info.

Napoleons comms network

The scam was uncovered in 1836, when the crooked operator fell ill and revealed all to a friend, who he hoped would take his place.The pioneering misuse of the French network qualifies as the world’s first network communications hack.