Crusader Kings II

[Monk]

When do the Crusades start in the current game? I'm a bit reluctant to go to war with a huge Muslim faction over one miserable county... Not that I can't beat them, but the micromanagement of the army is intense.

The Crusading Era begins in 1090. Anytime after that can spawn a crusade. The First crusade usually begins (in my experience) around 1100. But i've seen the AI call in 1090 right as it had its first chance.

Muslims can call Jihad any year after 1187.

Pagans and Zoroastrians can launch Great Holy Wars any time after 1100.