Why some factions cannot be "subjugated"?

[RobiePAX]

I'm trying to understand the subjugation mechanic. Why I can subjugate some factions, but can't others? For example here I capture Gaul's last settlement, when I attacked I merely wanted to subjugate them but the option was missing. I thought maybe this was not their last settlement, but no the following pop-up message notified me that 'Gaul's were destroyed".

Captured Gaul's last settlement[i.imgur.com]

Right now I have a theory that you can only subjugate your own "ethics race". So Romans only Romans, Barbarians only Barbarians, Easterners only Easterners. Can anyone approve if this theory is true? I have my doubts about it since you can still make a faction your Puppet State through Diplomacy despite their ethics race.

[Voth]

Your theory, however sound, I believe is untrue. It's a simple case of death before dishonor. Some factions would rather die than subjugate as far as I can tell. It probably stems from faction leader's traits inducing a percent chance of having a death before dishonor reaction.

I have subjugated Roman factions as barbarians. Tho this is just my theory and subject to error as well.

[Mikey]

if a faction is fighting against seperatist rebels they cannot be subjugated

[Mephiston87]

im playing ERE and had the choice to subjigate the Sassanids, was a tough decision but i decided to kill them, happening to theyr puppet states aswell. All of them so far iv had a choice to subjugate.

[karnage10]

If i remember correctly "gaul" is faction that emerges from settlement rebels , as such, it's a faction that cannot be subjugated.

[RobiePAX]

Originally posted by karnage10:

If i remember correctly "gaul" is faction that emerges from settlement rebels , as such, it's a faction that cannot be subjugated.

Interesting, I'll consider this idea. Though in the past I DID subjugate factions which originated from Rebellions.

[Voth]

I have subjugated gaul as the vandals and visigoths.

[ztac_dex]

same problem I can't subjugate anyone for some reason (subjugate button missing) I was able to subjugate the emerging faction on different runs tho

[David]

I am playing the Huns and subjugated every "race". There is no relation. When i invaded Persia i could not subjugate Sassanids vassals but when i subjugated Sassanids all vassals had to make peace with me at once and they had to help me in wars if Sassanids did so, cause Sassanids were subjugated by me ;).