Rome

The Black Death was one of the most harmful sicknesses in human history, causing deaths of about 75 to 200 million people in Europe in the 14th century. people think the Black Death started in the arid plains of Central Asia, where it probably travelled by the Silk Road, getting to Crimea. From there, it could have been carried by rat fleas on the black rats that were often on merchant ships. Overall, the plague could have taken the world population from about 450 million down to 350–375 million. The world population didn't go back to what it was before until the 17th century. The plague came back every now and then in Europe until it finally went away in the 19th century.The plague made a lot of religious, social, and economic canges in society, which had large effects on European history.