My guess is having a Monarch killed would result in a hefty on the spot prestige hit - and I'll bet good money that having negative prestige, in the middle of a war, while choosing a new Monarch is a big-time bad thing.
(Ie. Dynastic crisis, increased war exaustion, forced peace treaty, large loss of warscore. Ooooh the possibilities!)
Gezeder
(Ie. Dynastic crisis, increased war exaustion, forced peace treaty, large loss of warscore. Ooooh the possibilities!)
Gezeder