As I started my writing day on the Cannara onion farm, pondering the type of communications which might occur in 13th Century Europe, I went to Google.
There, in a learned tome, I found that there were two types of post/mail communications in this era. In two hundred years or so they would be replaced by governmental services of various countries. And such enterprise would be restricted to the state, so the government would make the money.
These two systems were organized by 1) business/commercial entities and 2) monasteries. In the preceeding few chapters, I had one of my characters, Matzerath, engaged upon a commercial venture taking him from Italy to London. Along the way he was to visit his mother. Unknown to him (and, until she did so, unknown to the author), his mother had become a religious hermit. And she was living within the confines of a monastery.
So now - of course - it will be the Cannaras who are instrumental in beginning a combination of these two forms of mail.
Historically, there was a superb state mail service at the time of my first novel. Then the Roman Empire fell and so did such services. And now, in the time of this novel, methods of postal delivery are coming back. If Matzerath's mother had never gone to the Monastery, I would be absent this vibrant plot thread. These types of oddities happen often enough in my writing that I sometimes feel a cosmic force allows me to enter. I am allowed a toe in that river Heraclitus tells us is never the same. But once in awhile it is. spartanmail.uncg.edu