Can somebody please explain what happened here?

[Goodfontana]

I have only around 700h in the game and something really strange just happened:

I'm playing Byzantium going for the Basileus achievement. After taking out the Ottomans, the Balkans up to Bosnia and couple wars with the Mameluks, I'm fighting the Timurids who, without the Ottos, have grown of control, with the help of my good ally the Commonwealth.

In the middle of the war, my 23 y/o leader dies, no big deal, I go into a regency, but suddenly, the following month, out of nowhere, I get a notification that the Commonwealth declared war on me. Two of our armies where in the same tile after taking out a Timurid army and start fighting each other immediately.

Turns out that I have just PU Austria, during a regency, having a different religion, not having the same dinasty, and the Commonwealth has contested it.

Can somebody please explain how is that even possible? I did have a royal marriage with them, but that's pretty much it. No shared dinasty, my regent is female (I assume that's the reason why Austria can no longer be holy roman emperor and lost it to Saxony lol) and I was in a common war with the country that is now contesting the PU.

 

[JacobiteJames]

I have only around 700h in the game and something really strange just happened:

I'm playing Byzantium going for the Basileus achievement. After taking out the Ottomans, the Balkans up to Bosnia and couple wars with the Mameluks, I'm fighting the Timurids who, without the Ottos, have grown of control, with the help of my good ally the Commonwealth.

In the middle of the war, my 23 y/o leader dies, no big deal, I go into a regency, but suddenly, the following month, out of nowhere, I get a notification that the Commonwealth declared war on me. Two of our armies where in the same tile after taking out a Timurid army and start fighting each other immediately.

Turns out that I have just PU Austria, during a regency, having a different religion, not having the same dinasty, and the Commonwealth has contested it.

Can somebody please explain how is that even possible? I did have a royal marriage with them, but that's pretty much it. No shared dinasty, my regent is female (I assume that's the reason why Austria can no longer be holy roman emperor and lost it to Saxony lol) and I was in a common war with the country that is now contesting the PU.

You can get a pu without sharing dynasty, just sharing dynasty increases odds of pu rather than dynast
Religion doesn't matter

 

[lilunxm12]

The PU system sometimes just weird. I'm more curious about how could commonwealth declare war on you when you two are on the same side of same war? I thought that's impossible.

 

[PDXJon]

Are you Austria”s rival?

 

[Terixis]

PUs make the AI do strange things sometimes. Like every country you're allied to and have a royal marriage with going domineering and breaking their alliance with you if you introduce a weak claim heir.

 

[LSF]

I doubt it is WAD, should go to bug report, because 2 tags sided in a war cannot enter another war in opposing sides.

 

[Jespoke]

This is a longstanding design oddity around PU wars, they instantly white peace the contestor out of any wars that would cause them to be on the same side as their new enemies. No. Matter. What.

I once got stuck fighting a war France started and France contesting the Burgundian Inheritance at the same time, because the PU war peaced France out of their own war without ending it for their allies...

 

[bokorthedust]

The PU system sometimes just weird. I'm more curious about how could commonwealth declare war on you when you two are on the same side of same war? I thought that's impossible.

The war is declared automatically if he contests the PU, while the mechanic you're talking about is only for manual war declarations. As others have said, it's a quirk of the PU mechanics.

 

[LSF]

This is a longstanding design oddity around PU wars, they instantly white peace the contestor out of any wars that would cause them to be on the same side as their new enemies. No. Matter. What.

I once got stuck fighting a war France started and France contesting the Burgundian Inheritance at the same time, because the PU war peaced France out of their own war without ending it for their allies...

Wow, I never noticed it, this automatic white peace. And your example of a white peace of war leader with war going on with other participants is just pure craziness.

 

[SirGregMac]

As detailed in the late great Atwix's guide to PUs, you don't have to have a RM or same dynasty as another nation to get a PU. Similarly claiming another nation's throne because they have the same dynasty and a RM doesn't mean you'll get them under PU if they die heirless, but it does make it so that you'll be the defender in a succession war, making victory much easier if you don't declare war for their throne prior. Most of that doesn't apply to this situation, but my guess is you were a rival of theirs which meant you were one of the possible claimants, though that can rotate between rivals/enemies.

 

[Goodfontana]

Most of that doesn't apply to this situation, but my guess is you were a rival of theirs which meant you were one of the possible claimants, though that can rotate between rivals/enemies.

No I wasn't, I was in fact allied to them and the Commonwealth.

Thanks everyone for your comments, I guess what happened was possible but it certainly had very low chances of happening. I'll bet you anything that if I allied and RM Austria intending to get a PU for free it would've never happened