The Black plague started in South Asia and spread around the world in the late 1340's. Many died over 1/3 of the world population.
The prince and his solders decided to kill off the merchants by throwing over their dead men infected by a deadly disease.
The merchants flied the place and sailed of to their homeland without knowing that they were spreading the disease.
Every time they docked they spread the disease they were soon unable to dock due to them being rejected due to the sick sailors on board.
The pope and those who had faith in the church started to pray to God to stop this plague, and some prayed that his rage on mankind would stop and he will forgive us.
Soon the sickness now known as the Black Plague had spread through Asia and Europe and millions apon thousands had died within 3-5 days. Very few preists still gave the dead victums their last rights to life and were often descarded in farmlands not even properly burried due to the amount of bodies they got dayly soon there was no more land to burry the dead. There was only one preist that was brave enough to give the dead their last rights.