Incredibly unlikely, definitely some kind of ASB, but nonetheless fascinating.

The premise for the scenario is during the 900s, during a period of corruption in the Catholic Church, the Byzantine emperor, Nikephoros II Phokas, announces his conversion to a surprising religion – Buddhism, to which he was introduced by a group of wandering monks. He proposes that as well as accepting Jesus as the son of God, they accept the Buddha’s teachings as equally divine and adhere to them as well. Naturally, there is uproar – while most of his empire accept this, a small number resist, and after a brief civil war, are exiled. The Pope is outraged, and despite attempted negotiations between the two parties, they cut off all ties with the Byzantine Empire.

Over the next century, a lot changes. The early Georgian Empire is converted, and in 1068, along with Muscovy, the three nations create the Pax Budesci (peace of the Buddha), an alliance of Buddhist nations. In Europe, tensions stir against the Byzantines, and in two Crusades, war is briefly declared, but soon ends with no clear resolution.

In the mid-12th century, a Third Crusade is declared against the “heretical” Byzantines. Here, the Pope actually seeks the assistance of the Islamic nations, who are promised, in exchange for fighting alongside the Christians and also a small enclave around Jerusalem (to be given to the Church), all of the Byzantine and Georgian Empires. As a defence of his action, the Pope states that as monotheists, the Islamic and Christian nations should be allied.

At first, due to an insufficient army and navy, the PB begins to fall, and for half a century, they barely manage to hold out. Fortunately, at this time, the Buddhist nations of Eastern Asia – the Mongols in particular – come to their aid, and the Byzantines are soon victorious. The Islamic nations are defeated and exiled to the tip of Arabia and Africa, while soon following the collapse of the Mongol Empire, its former territories are quickly incorporated into the Pax Budesci.

Despite losing half of the Balkans, 1300-1600 becomes known as the “Budescan Golden Age”. Its explorers colonise the steppes of Siberia and travel as far as the Pacific, while building magnificent cities and pioneering technology across its cities. China, however, refuses to join the alliance – organising itself into a “Triple Kingdom” ruled by three emperors, and retaining Korea and Japan, their explorers found trading posts in Kamchatka, the Aleutians and even North America – in 1505, a “Great Expedition” travels as far south as San Francisco.

In 1481, the Americas are discovered by accident, and Europe rushes to claim it, hoping to consolidate its own power to rival that of the Byzantines – the Incas and Aztecs are defeated quickly, and their territory populated by western settlers.

In 1521, an underground movement akin to Protestantism begins in Denmark, and quickly spreads across Europe, even into Italy. Naturally the peace cannot stand, and in 1554, war breaks out.

I may continue the map to show this in detail, but I am not sure yet.