In Victoria 2 there was one heavily overlooked region that was in anticolonial war and struggle, with a brutal half-a-century long war being conducted there against the native population.
That region is Caucasus.
What is Caucasus?
Caucasus is a region that often is commonly overlooked or looked up only for the Great Armenia memes.
Caucasus isn't just Georgia, Armenia and Azerbaijan either as quite a few people unacquintanced with the subject may think. It's also a lot of smaller nations that lie not just on Southern side of Caucasian mountains, as the today independent states are, but also a lot of North Caucasian nations - Chechens, Osetians, Avars, Dagestanis, Cercessians and others (and they are divided into many sub-ethnic groups too). Prior to XIX century, these lands weren't populated by Russians at all... until the Russian Empire started to annex Caucasus and the Caucasian War happened.
What is the Caucasian War?
Caucasian War is a group of conflicts tied to the Russian Imperial expansion into Caucasus and annexation of the subjects it controlled. During nearly all it's duration it faced insurrections, local conflicts. An oppression against the natives occured and, in the final stages of the war, an ugly ethnic cleansing.
The war started with establishing control over things which Victoria 3 would define as Unrecognized States - different smaller Caucasian states, where Russian Empire became their overlord. It is similar to what happened in another ethnically diverse and heavily fractured region, India. The Russian Empire then proceeded to take control of this region more directly. In 1801 was annexed the main Georgian state, Kingdom of Kartli-Kaheti. The other annexations of smaller realms then followed.
The establishment of the Imperial Rule, however, was met negatively by the native population. Unlike in the case of India or Georgia, where many local feudal lords were integrated in the systems of colonial rule, it didn't happen to other Caucasian nations, primarily the North Caucasus. This escalated... and the religious and feudal elites supported the anti-colonial war against the Russian Empire.
The campaigns of the Caucasian War were brutal. Many Russian Intelligentsia took part in it as well because the dekabrists were forced to serve in Caucasus; quite a few other reknown Russian writers took part in it (directly or were in Caucasus at the time) - Mikhail Lermontov, Alexandr Griboyedov and Leo Tolstoy; Pushkin was writing about the Caucasian War as well, making it an important public affair. The Caucasian War saw participation of Polish fighters, who were inspired by the anti-colonial struggle and united in desire to end the Russian Empire.
Caucasian War in 1836
1836 starts right during the 2nd period of the war, right before Imam Shamil started to organize his actions and "his" period of this war. Imam Shamil is the most reknown leader of this war and one who had an immense influence on the following history of the Caucasus. It's the most important part of the Caucasian War and it's subconflict, the Murid War, that had the lasting impact on the region. The year 1836 presents many opportunities for this war and allows some divergence in outcomes, as well as making the player pay attention.
How do I suggest to model this conflict in Victoria 3 and why do I think it would work out better than in Victoria II?
Right now, from few small glimpses into the teasers, we know that Victoria 3 has new special mechanics to represent not "civilized" nations - Unrecognized States and Decentralized States.
In my humble opinion, the best way to represent this is to represent the Caucasian States as the Decentralized States that are actively hostile to the attempts of colonization by the Russian Empire. They require a number of military action to be performed, but at the same time they will conduct warfare during the occupations or have "raids" performed on them. Perhaps a minor form of partisan conflict will be implemented to represent it (similar to what happened in Americas, African colonies including the British expeditions in South Africa, etc) which could also perfectly work for the representation of the Caucasian resistance.
Of course, North Caucasian societies weren't as tribal as Amazonian ones or some African ones and were certainly more developed. They were in fact sufficiently centralized. However, such form of representation as a territory that should be "properly colonized" rather than taken in a single short war could be a far better representation for them. To amend their status, the North Caucasian tags could get a special condition for getting Recognized and transferring from getting Decentralized to, well, Normal. It is all assuming that the colonization of the Unrecognized states happens as a result of short wars. Also, have you been in Caucasus and seen how many hardly accessible mountains are there? With hostile natives it's not easier than with malaria.
Why Caucasus region is important?
Because Caucasus holds the strategic defense for the Russian Empire from the South.
Caucasus is instrumental in Russian access to Persia; the Central Asian route can't really substitute it.
A lot of local historical trade routes passed through Caucasus.
And of course, it is a region that is quite contested by Turkey, Russia and Iran. It has a major geopolitical value regionally, controlling the mountains and influence there would mean having an edge over the other local players.
Why it is important to represent Caucasus region?
Because the history of Caucasus is sadly often forgotten by the common public. It's often neglected as the colonial expansion of Russia.
After all, we can clearly see the coloniasm (in XIX century) portrayed as American expansion to the West and fighting Natives, African colonization, Oceania colonization and the subjugation of the Unrecognized States (in new Victoria 3 terms) by the Recognized States and European nations. Even Central Asia is seen as a colonization and represented as such in Victoria II.
However, Russian conquest of Caucasus isn't perceived as such.
Russian society of the XIX century largely percepted it as the colonial war and the colonization of the Caucasus. As noted above, intelligentsia and the famous writers wrote about it as such. It doesn't mean that they saw it as unjustified, as XIX century didn't have the negative attitude to the colonialism yet, and even today the historians in Russia consider it to be justified (akin to the American expansion to the West against Natives). The Caucasian War in essence was the colonial conflict and aimed to subjugate the local nations; it was a colonial conflict and perceived as such in XIX century; it was a bloody war in 1800s-1860s.
Victoria 3 will do it's best to represent the colonization against the Natives and it won't shy away from the dark pages from history. However, while countless historians in Youtube and other popular platforms talk about coloniation in America, Africa and in particular colonization against the Natives in USA, absolute majority of them neglect to mention Caucasus at all, which was in most ways the same conquest and colonization... and ironically it ended in similar way, with an ethnic cleansing of natives by forcing them to relocate to Kuban' and Anatolia away from homes.
It's a quite important story. It made a big point for Russia, tied it's hands in the terms of colonial expansions (as it was represented in Victoria 3 to be not tied to such things which wasn't true) that had a strategic meaning (no rush to Africa, Central Asia or Far East to paint Japan or China before everyone) and made it want to retain control over the region firmly against the enemies - Persia and Ottoman Empire.
It's because of this I would love to hope that
@Wizzington and his team are going to do justice to Caucasus and represent it no worse than American Natives, making the principal decision to represent Caucasusian anticolonial struggles. It may be abstracted at first, with certain generalizations, but the core decision about representing it should be made.
About few minor details and Unrecognized Nations
One of most interesting ones that tend to be overlooked are in Caucasus - Megrelia, Abkhazia and Svaneti were annexed around 1860s. They weren't the autonomies like Finland; in fact, they were Unrecognized States and Protectorates of the Russian Empire. In general terms they had a function similar to the Indian dependancies of the British crown. And unlike the rest of Georgia and Armenia with Azerbaijan, these principalities remained as protectorates. It was partially related to the unrest in Caucasus and the Caucasian war - the stability of the sea regions was seen as crucial and Russian Empire delayed annexation in order to buy loyalty and stability from locals.
In the context of the larger colonization of Caucasus, representing these protectorates could further remind us of the colonial nature of the Russian expansion in Caucasus and give more possibilities for the Caucasian states that are still not absorbed in 1836 to attempt to win the anticolonial struggles - most likely with the foreign help of course, historically Crimean War came close to becoming such an event but Russian didn't lose war in Caucasus.
Conclusion
A proper representation of colonialism and anticolonial struggles in XIX century is impossible without representing Caucasus.
In Russian culture, the wars in Caucasus and it's subjugation left a lasting impact on the culture and public perception of XIX century.
It is no less important settling the faraway Oceania provinces, Africa, and other places.
It's not just a minor region that can be added with modes, it is a core part of the Russian expansion history and Middle East influence, including the next influence on Ottomans and Persia.
