Crusade target vanishes; what happens to crusade?

[scaddenp]

Italy is being a pain. Created a crusade with target of
Constantinople. However it has immediately gone in opposite direction, hoovering my troops from Burgundy, Provence etc. I don't want war with Italy
at moment and could juggle troops around to minimise impact but...

Attacking the Turks WOULD suit me fine and I am far better placed than
Italy to take out Constantinople. If I raise catholic flag over the crusade target, what happens to Italy's crusade which in now deep in my area?

[HopAlongBunny]

If it's a target for your crusade. the crusade will likely (not always) disband. An AI crusade will march to your new held territory and demand you hand it over. Refusing starts a war, and most often excommunication.

[Zarax]

Fill the area with the chapter house with spies, once the territory will rebel there will be no crusade and you can launch your own.

[Armchair Athlete]

If you manage to get the conquered province which was the crusade target to at least 50% caltholic, then the enemy crusade will disband - the message is that the province has returned to the catholic fold and the crusade is now disbanded. The enemy still loses one influence, but gains all of the troops from the crusade. This is pretty hard to do usually, you need high valour bishops and probably a province with a church or monastery nearby.

[Darius]

Ok one time my crusade army had a prince in it. When the target was taken by the french, they disappeared. Now the strangest thing was that later on, I found my prince....as a mercenary. He still had the little silver prince thing and his royal knights and everything, but also the little merc symbol. It was so incredibly bizarre.