Unify the steppe first
1206 as a political prerequisite -- a historical observation.
Campaigns followed political insult, succession, and seasonal grass. The 1241 European ride and the 1258 Baghdad campaign are the two western names English readers know; the Goryeo war is the one Korean readers know.
Failed amphibious war against Japan is the limit-case of a land empire at sea.
Principles
Cities can be destroyed or taxed
The chronicles show both outcomes; historians argue the pattern.
Succession interrupts campaigns
1241 and 1260 as exhibits.
Sea is a different problem
Japan 1274/81.
Empire splits into governments
Khanates, not an eternal horde.
Steps
- Unify
1206: a steppe state with a name.
Title first, then the long war.
- Break neighbours
Xia, Jin, Khwarezm.
Each war taught the next chroniclers terror.
- Ride west
1230s-41: Rus' and Central Europe.
A campaign that ended with a funeral in Karakorum.
- Take the caliphal city
1258 Baghdad.
A political end more certain than any death integer.
- Hit limits
Ain Jalut, Japan, stubborn Goryeo then submission.
Edges are part of the story.
- Become dynasties
Yuan and khanates.
Conquest that lasts becomes tax.
Diagrams
A split diagram after the 1260s -- the honest map.
A schematic of Goryeo yards to Hakata -- the East Asian inset.
Limits
Numbers
Global totals are bands; some chronicle figures are rhetorical.
Source bias
Winners' later Yuan histories and losers' city laments need each other.
No how-to
No raiding, siege, or command instruction.
Siege stories are chronicles of terror and negotiation. They are not instructions.
Withdrawal in 1242 is a political-military fact, not a miracle tale only.