Greatest 'could-have-been' Empires

Mexico. Though interestingly enough I think in order to do that you wouldn't so much have to focus on changes in Mexico itself, rather changes elsewhere. Specifically the United States. Prevent, split, weaken the US significantly (many opportunities for this) and a Mexican Empire free of American influence could become a serious power.
 
Palmyra, (ancient) Ghana, Korea, Hungary-Croatia, Niswimishkodewin - these are some empires that I would really like to see in ATLs.
 
Although ancient/medieval East Asian history is one of my least well-known topics . . .

That's fine. I'm glad that you're willing to learn.

. . . I think that a Korean polity could've dominated Manchuria and Japan IF:

-They were involved in Japan prior to the Shogunate.

They actually were, specifically from AD 300-660, as Goguryeo, Baekje, and Gaya had close connections with the statelets in the archipelago, and cultural influences continued into 900, as former Baekje aristocrats continued to guide Japanese administration, while Balhae maintained its diplomatic relations with Japan until its sudden collapse in 926. However, further influences require unifying the peninsula before 500 and integrating Manchuria beforehand in order to signficantly strengthen its position within Northeast Asia.

-They utilised well their turtle ship and gunpowder advantages.

This would require a unification during the Three Kingdoms Period, along with retaining Manchuria in order to consolidate it further, as stated above.

-Built a Great Wall analogue to the West of the Amur, preventing raids by Mongols and Turks.

This also occurred when Goguryeo built the Cheolli Jangseong (Thousand-Li Wall) near the Liao River under Yeon Gaesomun's supervision, who eventually staged a coup in 642, and Goryeo later also built unrelated fortifications with the same name significantly north of Pyongyang. However, the Goguryeo one was built from 631-46 to repulse potential invasions/raids from China (Tang), and the latter from 1033-44 against the Khitan/Jurchen. On the other hand, the Turks never invaded Korea, although they allied with Goguryeo against China and helped to establish Balhae afterwards, while the Mongols didn't seem to have any trouble passing through the latter wall when they relentlessly invaded during seven campaigns from 1231-57, causing the weakened court to nominally surrender in 1259, although sporadic resistance occurred until 1273 under a disgruntled military faction.

-Possibly work with local Ainu allies to weaken Japanese resistance, depending on how early we're talking.

Again, this requires unifying the peninsula and retaining Manchuria first, in which any influence must come from the north, presumably through Sakhalin.

However, it's important to note that it would be extremely difficult to directly govern both Korea and Japan simultaneously for more than a few centuries due to logistics. As a result, it would probably be more likely for Korea to exert a strong cultural influence on Japan after 1000, although this would also occur simultaneously with the Chinese one.
 
Tibet, Serbia and possibly a Georgia or Armenia

I don't think Serbia is actually in a very good position to expand though. I think that if they were the Dusan borders, it would be possible, but any later Serbia is too small and too hemmed-in, particularly by Hungary and whatever polity, Turkish, Latin or Greek to the South. The Balkans is a terrible place for power-projection.
 

Avskygod0

Banned
I don't think Serbia is actually in a very good position to expand though. I think that if they were the Dusan borders, it would be possible, but any later Serbia is too small and too hemmed-in, particularly by Hungary and whatever polity, Turkish, Latin or Greek to the South. The Balkans is a terrible place for power-projection.

Pretty much this
 
Niswimishkodewin is an Ojibwe word, and means 'Council of the Three Fires'; it was a confederation of American natives, founded at the end of the 8th century and mostly located around the Great Lakes.

Oh okay. I'm aware of the Ojibwe peoples, but I googled Niswimishkodewin and couldn't find anything. Thanks for the explanation :p (learn something new every day on here)
 
Ah, I have another one: The Irish Empire. With a PoD in 1014, Brian Boru survives the Battle of Clontarf and subsequently unites the island. Various invasion/incursion attempts on Ireland fail, the Irish themselves eventually expand to Great Britain, and slowly -over the course of the next centuries- incorporate and assimilate all the people of the British Isles into the Irish culture.
 
1. Song dynasty with a militarily talented emperor utilizing its technology and economic prowess to conquer the Liao dynasty and industrialize early by making use of the huge coal reserves in Siberia.

2. Ming dynasty where Zheng He's expeditions continue, sea trade is encouraged and the empire spreads to every direction, including the Americas which has abundant resources.
 
-Anything on Persia. Especially the Achaeminids.

-India too. The Kerala region always struck me as a perfect place to start a Indian Ocean empire. In fact, why didn't any Indian culture develop seafaring traditions?

-Indonesian states could have colonial empires too. Though I'm fuzzy with the details.

-The Incas were pretty big as they were already. They could probably start to colonize Argentina and Colombia with a delayed Columbian Exchange.

-Siam?

-And I'm not sure, but weren't there large empires in Africa too? Mali and Shongai to say the least.
 
In fact, why didn't any Indian culture develop seafaring traditions?

Because if they had focussed on building a seafaring empire, they would have been too weak on the mainland to defend themselves against their Indian mainland rivals; if they had focussed on defeating their mainland rivals and uniting the subcontinent instead, their administrative control would have been stretched too thin to effectively build and control any island colonies.
 
Indian Cultures developed Seafaring cultures. How do you think Hinduism got to Bali? The Chola Empire comes to mind.
 
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