How Do Holy Wars Work?

[SacremPyrobolum]

So I am on Alexiad Byzantine Playthrough #19 and I things are going real well, Seljuks collapsed and now the major powers where they used to be near me is Syria and some weird Messalian heresy Levantines as well as Shia Egypt and an independent Shia Jerusalem.

What I first thought was pretty weird was not being able to declare a holy war against the Messalians. They are Christians, sure, but they are a heresy and are also pretty fucking weird. Second off, I cant declare a holy war against Shia Egypt or Shia Jerusalem. Is this because I don't boarder them?

 

[Rylock]

What I first thought was pretty weird was not being able to declare a holy war against the Messalians. They are Christians, sure, but they are a heresy and are also pretty fucking weird.

They are a Nestorian heresy, not an Orthodox heresy. To you, they're just as good as Nestorians themselves.

Second off, I cant declare a holy war against Shia Egypt or Shia Jerusalem. Is this because I don't boarder them?

Likely. You need to border or have a province that is very close, like across a small water channel.

 

[SacremPyrobolum]

Shouldn't I be able to Holy War against Nestorians" Its not like they are as well established and Catholicism or anything, and even if I did have some tolerance for them, this heresy seems like it should tip it over to "Deus Vult" territory.

 

[Rylock]

Shouldn't I be able to Holy War against Nestorians" Its not like they are as well established and Catholicism or anything, and even if I did have some tolerance for them, this heresy seems like it should tip it over to "Deus Vult" territory.

No. Like Catholics and Miaphysites (Coptics & Apostolics), there is no reason to holy war against them. They separated due to a schism a long time ago.