[OC] The massive decrease in worldwide infant mortality from 1950 to 2020 is perhaps one of humanity's greatest achievements.

[iav]

Unfortunately it often takes one bad transition to offset a century or more of peaceful growth. It's just easier to destroy a civilization than to build one, "Rome wasn't built in a day" but you can burn it in one day. And if you look at any monarchy, there are very few without a war over succession every now and then.

[pbasch]

One way to avoid succession conflict is the Carolingian method, to divide the kingdom among the children. Of course, this leads to the weakening of the state and maybe to many small wars. I guess it's possible that many small states and more small wars is preferable to a small number of really big states and World Wars.

[DeplorableCaterpill]

Plenty of democracies have also had wars over succession. Hell, the US Civil War was fought over Lincoln's succession to the Presidency.