How were birds (pigeons, ravens, etc.) trained to deliver messages back in the day?

Question

How were birds (pigeons, ravens, etc.) trained to deliver messages back in the day?

In: 4193

Answer 1

They weren’t.

The specific types of birds they used weren’t trained to take messages.

Rather, these birds wanted to return to where they were born, their home.
So, you would birth some carrier pigeons, then, take them to a place you wanted to receive messages from (or, someone else would take them to a place they wanted to be able to send messages from).

Then, when you want to send a message, you select a pigeon born in that place, attach the message, then, let it go. It flies home, and your message is delivered.