Hello,
Currently I'm playing a campaign as the HRE and I think I've been doing fine: during early game I managed to conquer Northern Italy, modern-day Poland and the Low Countries, made alliances with the Papal States, France and Denmark plus have good relations with Hungary. I established a well consolidated empire in Europe so I decided to join a crusade to the Holy Land. I captured all the coastal regions from Adana to Gaza including Jerusalem, then took Cyprus from the Byzantine Empire as a retaliation since earlier for some odd reason the Byzantines launched an invasion against the Reich on Cagliari.
Then the Mongols showed up near Baghdad and started to migrate westwards towards my 'Crusader State' in the Levant. First they plundered Antioch then turned south and besieged Acre and Jerusalem. I managed to repel both their attacks annihilating two full stacks of their armies then it seemed they would retreat to the east. As I sent a spy on their tail, I noticed that four more full stacks were coming from the East to reinforce their armies.
As you can see on the map, there are 10 full stacks of Mongolian hordes gathering in the desert for a full invasion against the Holy Land. What would be the best method to repel the invasion? Should I fight them at the river crossing or in the mountainous terrain northeast of Jerusalem or just defend inside the walls of my settlements? What would you do in this situation?
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