Cultural/Tech Groups

Cultural/Tech Groups are the cultures of each country, each country has its own unique culture or shares the same culture as other countries, with each culture having its buffs and nerfs. Each country has its own nationality which they can enforce on other people with different nationality in that country's provinces by using cultural integration policies, making provinces your cores, the nationality of a province can heavily affect how strong rebels are in a province if they are not your nationality so be careful when you are taking a ton of non-cored provinces.

National Unity is a percentage of how many people in your country are your nationality, the lower it is the more aggressive rebels will be so use cultural integration policies to help you core provinces/transform them into your nationality.

 Different cultures also have their own bonuses, let take a example, the romans and the nomads:

The romans have smaller army size without the legion policy which they also get to maximize their army size

They also have a overextension bonus of 1x/1.50x meaning they get normal overextension which can help them expand more

They also have a tech bonus of around -30 years behind the current era, meaning they have decent technology

Now let talk about the Nomads, they have very high army size in early eras but in later eras their army size is very small because their technology is very bad, getting to that now,

They have a technologic bonus of -100 years, meaning their tech is very outdated than the current era

They also have a overextension bonus of 2x, which means they have to be careful when they expand as they can explode into revolts very easily.

Most of the nomadic countries also have very bad development, lowering their tax gain very much

 (THEY ARE EXAMPLES TO GENERALIZE DIFFERENCES BETWEEN CULTURES)