Typography was invented twice: once in China and Korea and in medieval Europe. In China, printing was invented, according to some data (Julien, "Documents...
The first invasion
The first officially organized invasion of North Africa by the Caliphate began in 647. After leaving Medina, 20,000 Arabs joined in Memphis...
In the Medieval period, every kingdom was at war, everyone was fighting against everyone and it was just a mess.
As technology developed a lot of things changed.