u/CommonSink7557

Had some great discussion on an earlier version on this (that version was removed, so posting it again, properly)

Petroleum exists but commercial refining is impossible. The investment goes into coal and electrification instead.

The first thing that is surprising is aviation. Without petroleum fuel, fixed-wing aircraft development stalls completely. What fills (or tries to fill) the gap is lighter-than-air. The age of the airship doesn't end in the 1930s and transatlantic airship routes are the standard for passenger travel by 1950s, and the development of hydrogen fuel cells was pushed two or three decades forward since the competing petroleum technology was absent.

The second suprise was Japan. Since Japan has enormous domestic coal deposits (that in our timeline were abandoned as uneconomical once oil became dominant),it is an energy-independent and a coal superpower with a different set of strategic interests. (They aren't desperately reaching for Dutch East Indies oil fields, for example)

The Middle East and whales are the other threads I am focusing on, and happy to dig them deeper.

(Long-form audio version on my channel in sleep video format — in bio)

(Second time posting this at was removed due to an AI image).

The point of divergence would be the Nicaean council. The council ends in a deadlock and Cyrenaic Arius of Alexandria is not exiled. He lives seventeen years longer than he did, trains a generation of students, and the eastern Roman Empire spends the next two centuries slowly becoming something that Muhammad would recognize when he arrived.

By the time Arab armies move north in the 630s, they're merging with the Roman provinces instead of conquering them (The theology had already drifted that far). Radical monotheism, no icons, daily prayers... The wars still happen but their motives are different in this timeline.

Rome falls in 752 through a naval encirclement and a negotiation. Pope Stephen III signs a treaty, debates for three weeks whether to stay and become a martyr or leave and keep the institution alive, and departs for Cologne. The Catholic Church is headquartered in Cologne for twelve hundred years.

The Pantheon is a mosque since 762. The marble mihrab in the southern wall that was carved by craftsmen from Alexandria, is considered one of the finest pieces of decorative art from the early Islamic period.

There is a small Catholic community in Rome. They hold Mass every year on 13 May at the portico of the Pantheon (the anniversary of its original Christian consecration) and have done so without interruption since 763 AD, one year after the conversion. The Islamic administration has never formally objected.

The Istanbul Bosphorus is the most contested strait in the world. Roman Islam on the west bank and Turkish Islam on the east bank. There is a hadith about Constantinople in this timeline as in ours. The Turks read it every generation and look across the water and feel something the theological arguments don't quite reach.

The Crusades happened to retook Rome permanently. The longest Catholic occupation was thirty-one months, 1187 to 1190. The Pantheon was reconverted during those months, the prayer rugs rolled up, a temporary altar installed. When the city was retaken the rugs went back down within two weeks.

I've been building this timeline for a while. Happy to go deep on any thread. The three-way tension between Roman, Turkish, and Arabian Islam is the most interesting ongoing argument for me, and I haven't even gotten to what happens in Iberia or Russia, or how the Crusades changed Catholic Europe culturally even as they failed militarily.

(There's a long-form audio version if you want to fall asleep to, link in profile)

The focal point of the timeline would be 325 AD. Council ends with the Arian win, presbyter Arius isn't exiled, and the eastern Roman Empire spends the next two centuries slowly becoming something Muhammad would recognize and embrace when he arrived.

By the time the Arab expansion begins in the 630s, the eastern provinces are actually merging with the expansion instead of being conquered.

This map shows roughly 1200 AD: Islamic Rome controls the Mediterranean south and east. The Catholic world has been pushed north of the Alps and is building into Germanic and Slavic territory instead. The Bosphorus is the most contested fourteen kilometers in the world with Roman Islam on the west bank, Turkish Islam on the east, the same hadith about Constantinople keeping the Turks looking across the water for another thousand years.

The Pantheon is a mosque in this timeline. The Pope is living in exile in Cologne. Rome has minarets above the Forum and a Catholic community of maybe two percent who have been holding Mass in Trastevere since before Muhammad was born.

(Full long-form audio deep dive on this: https://www.youtube.com/watch?v=X-Gf68PoqpQ&list=PLJQi5c2xFU2YkuaytayMQLcQ0nxQf6TEf)

Been building out this timeline for a while.
Petroleum exists but refining it proves unworkable. Coal and early electrification fill the gap instead.

-No internal combustion engine as we know it. Steam and electric rail dominate overland transport well into the 20th century.
-The Middle East never becomes a strategic prize. No Sykes-Picot carve-up driven by European oil interests. Any Arab uprisings against the Ottomans happen organically, and the Ottoman Empire probably survives into the 1940s in some form.
-WWI still happens since the underlying nationalist tensions are all there, but it looks very different without mechanized blitzkrieg.
-The US rises on coal and hydro, but the balance of power in the Pacific shifts. Japan’s imperial expansion changes character without oil as a strategic chokepoint.
Genuinely the rabbit hole that keeps giving. Happy to go deeper on any branch if there’s interest.