OTL
The Black Death was one of the deadliest pandemics in human history, peaking in Europe between 1347 and 1351. It is widely thought to have been caused by a bacterium named Yersinia pestis
The origins of the plague are disputed among scholars. Some historians believe the pandemic began in China or Central Asia (one such location is lake Issyk Kul) in the lungs of the bobac variety of marmot, spreading to fleas, to rats, and eventually to humans. In the late 1320s or 1330s, and during the next years merchants and soldiers carried it over the caravan routes until in 1346 it reached the Crimea in South Eastern Europe. Other scholars believe the plague was endemic in that area. In either case, from Crimea the plague spread to Western Europe and North Africa during the 1340s. The total number of deaths worldwide is estimated at 75 million people, approximately 25–50 million of which occurred in Europe.
The Black Death is estimated to have killed 30% to 60% of Europe's population. It may have reduced the world's population from an estimated 450 million to between 350 and 375 million in 1400
POD : the black death is much more virrulent than in reality, killing between 60% and 85% of Europe's population and killing over 300 million worldwide.
ATL : THE GREAT BLACK DEATH
In early 1346, traders in the city of Constantinople begin telling of a great plague that has infected peoples along the silk road to the east. Within 6 months people in the city begin to fall ill with fever and swellings in their armpits and groins, people who get ill are usually dead within 5 days.
In 1347 a Genoese trading vessel washes up on the southern coast of Sicily, all aboard are dead or on the verge of death, the local population salvage the cargo of silks and furs from India and then burn the vessel, little do they know that the fleas on the furs they carry back to their villages also carry the black death bacterium.
The disease outbreak in Sicily spreads rapidly and by August 1347 there are outbreaks of the black death in Alexandria, Rome, Pisa, Naples, Barcalona, Lyon, Marsaille and Athens. The plague spreads rapidly in the warm weather around the Mediterranian, by September 1347 the death toll has already topped 2 million.
By January 1348 the plague has killed over 10 million around the Mediterranian and is begining to spread north.
In May 1348 plague spreads into England and Ireland, it spreads rapidly and has infected the entire island within 18 months. Within 2 years, two thirds of the population is dead.
August 1348, only one year since the main outbreak of black death, the death toll is now above 75 million worldwide.
November 1348 in the northern countries infected by the plague begin to see a reduction in infection rates.
March 1349, infection rates in the northern countries increase rapidly, deaths are more likely due to the cold winter and malnutrition. death tolls worldwide now stand at 150 million.
During the summer of 1349 deaths increase as malnutriton spread across the world as few farmers still are working the land.
As the winter of 1349/50 encroaches, Pope Clement VI dies in Rome, along with King Edward III of England, Phillip VI of France and many other members of the European aristocraties.
Among the dead in the east are almost the entire royal house of Yuan in China, including Emperor Hui Zong. After the royal families deaths there is a rebellion in the south of the country and a new royal family (the royal family of Ming) are instated under the first Emporer Hong Wu (also known as Zhu Yuanzhang)
In January 1350 the new Pope Innocent VI announces that plague victims cannot be buried in hallowed ground, and more importantly no preists will give last rights (this is mainly due to the high mortality suffered by the church, as many as three quarters of the preisthood have already died).
During the summer of 1350 deaths from the plague tops 250 million worldwide.
By the winter of 1350/51 plague infection rates have dropped to practically nil, total death toll exceed 275 million, roughly 80% of the population of Europe have died with some areas around the Mediterrainian seeing death rates above 95%, many major cities around the coastline have been abandoned with the surviving populations moving to partially abandonded villages inland.
During 1351 there are several smaller outbreaks of plague in the large population centres worldwide, however deaths increase due to other outbreaks of diseases such as Cholera, Disantry and Typhoid. By the end of 1351 total deaths from plague and resulting diseases are above 300 million worldwide.
Due to the massive deaths in the religious faithful many people turn away from the Catholic, Jewish and Islamic faiths, in many places people return to the old pagan ways, mainly due to the fact that many practitioners realised the link between the flea bites and the plague and used insect repelants to reduce the infections. Only the areas around the Holy land and Rome retain the Christian and Jewish faiths and the area around Mecca and Medina retain the Islamic faith.
By 1370 the pagan faiths had become the dominant practice in England, Wales, Scotland, Ireland, France, Germany, Spain, Portugal, and Scandinavia.
In 1387 an army of 12,000 loyal Muslims (almost two thirds of the world population of Muslims) attack the holyland. They are driven off and the majority killed by a unifed army of Jewish and Christian defenders. After this point the Muslim faith collapses into small splinter groups and begin infighting amongst themselves, the Muslim faith ceases to exist by the early 1400's.
In 1396 and army of the followers of Jupiter (pagans following the old Roman gods) retake the city of Rome from the Christian defenders, Pope Urban II is publically executed on the Palantine hill, his body was then burned in the roman forum. All the churches in Rome are burned on the night of the 28th June 1397, St Peters Basilica (built by Consintine I) burns for 6 days.
By 1450 only the area directly surrounding the Holy land still follow Judism and Christianity, the total global population of the two faiths is roughly 122,000.