Usually the wars will be caused by conflicting dynastic claims but also be fought over a variety of other normally personal casus belli.
[1] In most countries it was traditionally considered the right of the nobility to fight personal feuds without incurring legal penalties, however the Kingdom of England was an exception due to its high level of royal power which could even go so far as to restrict tournaments.
[2] Usually feudal wars would involve both parties plundering each other's territories, skirmishes, sieges, and occasionally full battles.
[3] Often the leaders and participants of the feudal wars were related to some degree which helps explain the lack of casualties (to slay kin was considered much worse than to kill someone unrelated).
This list will not include religious wars because they are induced by ideological rather than personal or familial conflict.