Add on question to this: I have a feeling that the answer to op's question is to do with a lack of a country wide network where a 'fast' messenger could swap his horse for a fresh one and keep moving at high speed as his horses get exhausted. I don't have much more than half remembered old books to base that on, so I can't make a proper answer post.

What is the first recorded instance of one of these networks? Which ancient empire would it be associated with? And for that matter, how would large ancient empires communicate over long distances? Early Roman, Seleucid, Persian etc.? I'd imagine a system of speedy communication is vital for all large empires.

I know the British had an insular network of Semaphore towers during the Napoleonic period, was that a particularly novel solution to long distance communication or was it an improvement on the signal fire?

Edit: spelling/grammar

Maybe post the time he mentions it. That podcast is over four hours long.

Hiya folks!

Unfortunately, we're seeing a lot of low-quality answers which fail to meet our rigorous standards concerning in-depth and comprehensive responses. Doubly so for unfounded speculation, which has been pretty rampant so far!

Additionally, it is unfair to the OP to further derail this thread with off topic conversation, so if anyone has further questions or concerns, I would ask that they be directed to modmail, or a META thread.

Thanks all!