ORIGINS
The Black Death swept through Europe, the Near East, and North Africa in the 14th century. It was probably the greatest public health disaster in history. Europe and China lost two-thirds of their population.
The origin of the Black Death is uncertain-China, Mongolia, India, central Asia, have all been suggested. Historians generally agree that the Plague moved west out of the steppes, coming from China, and spread through Europe and the Middle East.

KAFFA
Kaffa was a Genoese city and port on the Crimean Peninsula of the Black Sea.
Kaffa (now Feodosija, Ukraine) was established by Genoa in 1266. It was the main port for the great Genoese merchant ships connecting trade with caravan routes linked to the Far East. In 1346, the Plague arrived at Kaffa, coming from Syria and Mesopotamia. It had originated in China in 1333.
The Tartars, enemies of Genoa and Venetian allies, sieged Kaffa. The people in Crimea were dying from Plague. In the first act of germ warfare, the people of the Tartar army fought with the only sufficiently available weapon at hand - the corpses of Plague victims. Using catapults the Tartars launched corpses infected with Plague over the walls of fortified Kaffa.

EUROPE
Four Genoese ships escaped from Kaffa. Ships travel to Genoa and to other European ports, carrying the disease to the heart of Europe. The Pestilence arrived with the surviving sailors and the rats with the goods of their ships. Terror established among the Genoese people when they realized the menace that had come to their homes. They had heard about Plague and then were witnesses to the horrible deaths of the victims of the Pestilence. In January 1348 the Genoese ships had carried the Plague to Venice, and to the rest of Italy.

RESULTS
In the 14th century the Plague spread across Asia and Europe with such force that the course of human history changed forever. When an infectious disease spreads to many people in an area at the same time, it's called an epidemic. When an epidemic happens in many cities at once, it's called a pandemic. The disease caused a pandemic.
People did not know what caused it and blamed many things including: sinners, planets and foreigners and Jews. Now we know that the cause was Yersinia pestis. Bacteria are microscopic. They can travel great distances, going quickly from person to person and even around the world.