The role wasn't a complete sinecure: the ruling warlord, Tokugawa Ieyasu, ordered the seppuku, or ritual suicide, of one of Koetsu's circle, the tea master Furuta Oribe, for some real or imagined disloyalty.
There are others that have aligned themselves with a local warlord, but at the same time don't present the type of global jihadist characteristics that one might see out of al Qaeda.