So the plague swept from east to west. I guess the first Euro cities hit would be those on the Mediterranean and possibly Moscow?
The Plague arrived by ship, stowed away on rats who spread it in Constantinople; it came from India — where it persists today — with which there was indirect trade via the monsoon winds and muzzie ships. There’s evidence that the infamous outbreaks during the Middle Ages were by no means the first ones in Europe, and they probably arrived the same way — during the so-called Dark Ages the already-ancient trade with India continued, and the Byzantine merchants traded all over the former Roman Empire, including Britain and into the Baltic.