Started writing a new alternate timeline with the end-goal being a stronger chain of Orthodox nations ranging from the Ethiopian highlands in the south to Muscovy in the furthest north. A kind of "counter-Christendom" or something in that vein.... I know the earliest changes I want to make in order to rebolster the Ethiopian Empire, but I'm not sure where to take it from there...
~525 A.D.
For centuries, Himyar, centered around the southwestern corner of the Arab peninsula, has been the mightiest of Arab kingdoms. But after its newest king, a fanatical Jew named Dhu Nuwas, came to power, he immediately began persecuting and exterminating the Christian and Pagan tribes in southern Arabia.
Incensed, the Byzantine Emperor Justinian I writes a letter to King Kaleb of Axum, the great Christian power of Africa. Roused to action, Kaleb sends forth an army of his warriors, backed by an East Roman fleet, under the command of two generals. First is the extremely capable but dangerously ambitious Abraha, second the indubitably faithful but less sharp Eriat. While Abraha's strategies handily win the battle for the Ethiopians, a fateful arrow to the eye kills him, perhaps to Axum's ultimate benefit. Dhu Nuwas, according to legend, commits suicide by riding his horse into the sea.
[Abraha's death is the first POD here. IOTL, he first declared independance from Axum after killing Eriat in a duel. He then defeated Kaleb's army, but accepted a place as a vassal-state while remaining the overlord of Arabia.]
Afterwards, an Ethiopian courtier, Sumuafa Ashawa, is proclaimed Viceroy in the name of King Kaleb. The garrisons at Zofar and Najran are reinforced, while some of the occupiers sail home across the Red Sea. Many, however, are encouraged to remain and settle, to replace the devastated Christian populace.
Following the death of Dhu Nuwas, the other Yemenite kingdoms---Qataban, Saba', and Hadhramaut, try to rebel. Each is in turn overwhelmed and subdued by Ethiopians over the next five or so years.
530-544 A.D.
During this time, immigration across the Red Sea is encouraged by the habitually insular Axumite kingdom. Projects to build up the culture of Christian Yemen are undertaken, as the Viceregality builds a Great Church, Al-Qulais, in Sana' and a new irrigation dam at the Wadi Marib. Another revolt in Hadhramaut is put down.
~569 A.D.
The events recorded as "The Year of the Elephant" come to pass in Central Arabia as the Axumites launch a 40,000-man invasion of the Hijaz. (The name comes from the inclusion of several War Elephants in the invading force). Sumuafa, a devout Christian, specifically intends to eliminate the Kaaba as a pagan shrine to rival his great church. According to the legend, Safua's elephants refuse to enter Mecca, and a flock of birds pelts his force with rocks until they retreat, even wounding the Viceroy himself. Whatever the case, the Axumite invasion is repelled and Safua dies of wounds on the way back.
[Note that I'm pretty much using Safua, an obscure figure who gets murdered as soon as he's introduced IOTL, as a stand-in for the actions of Abraha. The only difference is Safua acts as Viceroy, while Abraha was a client king. The point is Axum develops a greater attachment to Yemen and considers the defeats much more personal.]
570 A.D.
The dynasty of Himyar has in previous years managed to secretly make contact with the Persian Shahanshah Khosrau I. Pleading the tyranny of the Christian Axumites to the Zoroastrian King of Kings, Khosrau agrees to send a force which unites with the rebellious Arabs under King Saif Dhu Yazin. Together they drive out the Axumites, destroying the great cathedral at Sana'. However, Saif is assassinated (ironically by an Ethiopian mercenary who was his bodyguard) with no heirs, ending the Himyarite's dynasty. Thus the Sassanid General, Vahriz, is appointed Satrap to the Shahanshah.
Back in Ethiopia, King Kaleb has long since retired and his successor's successor Saifu reigns. According to popular accounts, Saifu spots a bright comet in the sky announcing the birth of Mohammed in Mecca to the Quraish Tribe. His envoys enter Mecca bearing gifts for the family. Nevertheless, the Negus and all Axum takes the loss of Yemen and its Great Church very hard---while they are not yet able to incur the wrath of the Sassanids, oaths of revenge are taken by the survivors.
615 A.D.
"Al Hijra" or, "The Flight," marks the first year of the Islamic Calendar as Mohammed and his followers are chased from Mecca after denouncing the idols and fertility rites at the Kaaba. King Ashama of Axum, Saifu's grandson, offers to grant the refugees asylum. The Quraish send an envoy, demanding the "criminals" be returned. Rather than giving in, Ashama asks of the Muslims to read from their Holy Book to him. After hearing a few verses from the Koran, he asks Jafar ibn Abu Talib (one of Mohammed's companions and leader of the refugees) about the Islamic opinion on Jesus. Rather than directly answer, Jafar reads from the Suras on Jesus (who is part of the succession of prophets and not Messiah to Muslims). Famously, Ashama draws a line in the dirt with his mace and says "the difference between us is less than the width of this line." Thereafter Muslims are welcome in Ethiopia, and communities spring up along the Red Sea coast in modern Eritrea. (Arab legends tell that Ashama later converted to Islam, but this is of course disputed by Ethiopian historians.)
627 A.D.
The apocalyptic war waging between the Byzantine and Sassanid Empires comes to a head with the Battle of Nineveh on the Tigris river. Having brought the Eastern Romans back from the brink of utter defeat, Emperor Heraclius famously kills the Persian commander in single combat and drives the Persians into their own country. The Shahanshah, Khosrau II, refuses to negotiate, leading to his murder by his own grandson in order to save the Empire.
With the Sassanids so severely weakened, and their capital buried in anarchy as coup follows coup, the Negus of Ethiopia at last sees his chance to avenge 570. Not the tolerant and kindly man his predecessor Ashama was, he intends to repay the destruction of the Great Church fourfold. Swiftly, the Axumite armies assemble and cross the Red Sea. Any in the Muslim communities who protest are swiftly taught the virtues of silence. The Sassanid Satrap in Himyar is overwhelmed as Zafar, Aden and Najran are retaken.
630 A.D.
Mohammed completes the capture of Mecca in a surprisingly bloodless finish to what had been such a bitter struggle. The Chieftain of the Quraish, Abu Sufyan, accepts that his Meccan gods have proven powerless and converts to Islam. Entering Mecca in triumph, Mohammed casts out the idols and sanctifies the Kaaba as the holiest shrine of Islam. In subsequent battles, he brings to heel the rest of the Arab tribes, uniting them all under Islam. Axumite Himyar is the last pocket of non-Muslim control in the Peninsula, and so at the end of that year Mohammed turns his armies south.
Remembering the kindness of King Asharma, Mohammed sends envoys to the Ethiopians, requesting they convert, or at the least, cede their power peacefully to the Arabs. They stubbornly refuse, and with a heavy heart Mohammed enacts the will of heaven and lays siege to their garrison at Zafar. Sure enough, the Arabs are victorious and the Axumites expelled from Arabia for a second time.
***
So, yeah, not sure where to go with it from here.... lots of ideas, with the ultimate goal being a powerful Eastern Christendom to check Latin Christendom by 1500 A.D.
-Obviously, this means reversing the final decline of the Byzantine Empire. I considered going as early as preventing the assassination of Maurice I, which would prevent the whole Byzantine/Sassanid war that left both weakened just before the Great Jihad. Didn't want to think of how extensively that would butterfly everything, though---Medieval Europe as we know it would probably never have come to exist, and I don't want to make that drastic a change.
-I also considered reversing Manzikert in 1071, but again this is thinking short-sightedly. The Byzantines did ultimately recover from Manzikert and become a power that had to be respected.
-The Sack of Constantinople, in 1204, however, is in my mind what broke the Empire's back and started its final slide. This must not happen. I don't know enough specifics yet, but I'm thinking to turn around the Byzantine Empire's 12th-Century defeats; the 4th Crusade should run into a powerful defense force led by experienced commanders at Constantinople, and get summarily crushed.
-It's also critical that relations between the Greeks, Serbs and Bulgars be repaired.... I'll have to see if I can find a book on Medieval Bulgaria or one on the wars between Bulgaria and Byzantium. Ideally they could work out something like a confederacy or a mutual defense pact.
-On the other hand, I can simply see no way to stop the conquest of the Kievan Rus by the Mongols. They were too disorganized and too few, and the Mongols simply had them beat in equipment and tactics. But with a strong Byzantine Empire able to cross the Black Sea, the "Mongol Yoke" need not last all the way up to 1480.
-Ideas I haven't really thought through yet... have things go worse for the Venetians in the many disputes between the Italian city-states in the 11th or 12th Century. They can't be a big problem for the Byzantines if they're fighting for their lives back home. OTOH, one of the other city states would probably simply take their place in trying to dominate the Eastern Mediterranean. The other half-thought I have is making the war between the Ottomans and the Timurids much more devastating for both, somehow, effectively leaving the east in ruins. Then again, a strong threat like the Turks might be exactly what I want to drive the Greeks, Serbs and Bulgars into a long-lasting alliance.
Thoughts, advice, criticisms would all be appreciated.
EDIT: Oh dear, this isn't the pre-1900 forum. Move plz? D: