Each and every player gives themselves a different goal in every playthrough of Victoria games. But most of those goals tend to gravitate towards becoming a Great Power, and this is how to do it.
Unlike in Victoria 1 and Victoria 2, where Prestige was just one of three factors determining what Rank a country had, in Victoria 3 Prestige is the accumulation of all factors that makes a country more or less glorious. In order to become a certain rank, a country must meet the Prestige threshold for that rank, which is based on both how it compares to the global average and percentile-wise compared to the most prestigious country.
The requirements to become a Great Power are as follows:
- Must be a Recognized country,
- Must not be a Subject of any other nation,
- Must have at least 3 times the average global prestige OR at least 75% of the prestige of the most prestigious nation.
This means two things: The number of Great Powers, Major Powers, and so on is not fixed to a specific number, as it was in Victoria 1 and 2, where you would always have 8 of each, and that the requirements to maintain and increase your Rank will change over the course of the game.
A country might start as a Great Power due to their starting prestige, but then begin quickly falling behind due to economic and military stagnation, eventually being reduced to a Major Power even though their actual Prestige number never went down.
So, as always, Diplomacy will be key in making your country Great Power. Of course, any sort of diplomacy from a position of weakness is merely protracted surrender, so getting that sweet stop between carrot and stick will set you towards your goal of becoming a Great Power.