We used (use) leadership in much the same way as Crothian. It started as a way to staff a keep with loyal followers (as opposed to the kind more prone to bribery, etc.). The cohort turned out to be a dire bear (later awakened and advanced) that lived in the forest nearby. One that served as a very effective guardian for the followers.
Recently, we used it to model a cult that has arisen around one of the PCs.
Recently, we used it to model a cult that has arisen around one of the PCs.