the black death / black plague originated in Asia after a earthquake disturbed some little organisms. they were on rats which had fleas that got infected and from there humans.
It started around where the red circle is and spread to about where the black circle is, and more.
Millions of people died.
there were people at war and they threw people who had the plague over the wall.
The people in the city started to die due to the plague and so they left. they thought they were safe. But the rats who had the plague climbed on board the ships as the ships sailed to different ports spreading the plague as they go.
Beat da Smeat
Lots of people died due to the plague. Or due to the merchants (mansions) as they sailed to different ports. In the end millions of people died and the plague moved on.