You could argue that the early use of smoke signals and drums by the natives were actually the first recorded use of telecommunications. They were used in much the same societal role as systems today - to send messages to, and communicate with, the applicable parties they wished to reach. Can you imagine the stress of primitive IT workers way back then? There was no such thing as an email registering a complaint; it was more likely a disgruntled colleague showed dissatisfaction by shooting the technician with an arrow or clubbing them over the head. Job security was fleeting.
While there were basic systems developed in the late 1700's through the early 1800's resulting in the creation of the semaphore system, that system itself was abandoned several years later because the towers were way too expensive and it was difficult to find enough operators that had the skill to actually use and manage it. The telegraph system, invented by Samuel Morse in 1844, is considered the earliest industrial iteration of successful telecommunications. Originally used primarily by the Post Office, the telegraph system actually grew and expanded along with the building of the railroad systems. These communication links were integral in moving goods and people from East to West and back again along the tracks. In many instances telco connectivity was established in an area before being followed by railroad construction. No wonder "training" is such a huge requirement for our industry! :-)