Answer:
The Black Death.
Explanation:
The Black Death report first recorded at Messina, in Sicily in 1347. The plague continued for three years and killed one-third of all the people in Europe. It began to spread in Europe through the trade route that connected the Black Sea to the Mediterranean Sea. The Medieval cities with the trading connection, effected by the epidemic as it was the centre of ports where ships arrived with infected rats. Many deaths occurred in the trading city-states, which were in the coastal region.
Answer:
Established a sense of patriotism and support for the war.
