I have read 10 pages in and found nothing obviously about this topic so....
What are their effects?
The reason I ask is that in my game my last two wars have been against two previous allies.
I am the Spanish and have been allied with the Italians and Byzantines for ages. The Italians married off their Princess to me on the third turn, the Byzantines in about 1140. I have alliances with almost everyone else except Egypt and the Turks.
I quickly killed the Almohads, then the French and Aragonese, so I owned all of Spain, France and West Africa. The Egyptians were losing a war against the Turks so I grabbed Egypt and Sinai easily. Then the Byzantines asked for alliance and were at war with the Turks. I agree by marrying a Princess, then help them wipe out the Turks, which is difficult and takes a while. About 1200 I start a massive build-up in preparation for the Golden Horde as I own Armenia and Syria and they coul be targets. In 1225 the Byzantine sink half my merchant fleet but don't attack any provinces because I heavily outnumber them. Everyone except Italy cancel their alliances with even though I was attacked, which is another question altogether.... Italy is at war with the Byzantines after snapping up Naples and Sicily.
It's now 1235 and Italy sinks some more ships and invades Greece with 300 Peasants????? Why would the country I am allied with against a common enemy attack me?
What do alliances do? Obviously not prevent attacks. What determines who stays allied with you when war breaks out? I lost alot of allies when the 1 province Danes attack me in Sweden, when I have the largest empire, income, tech, army and a king with 7 influence?
Do you get more trade from allies? Can your spies and assasins move through their territory without getting killed by Border Forts?
I do know that allied armies will fight for you if you happen to attack the same province on the same turn, but that is all and such a rare occurence.
Any light shed on this will be helpful.
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