Here is a quick tech tree of how a suggested tribe could evolve after the prelude.

Example: [NOT A SUGGESTION, JUST AN EXAMPLE OF HOW ONE COULD TAKE IT, to ensure this, I made a pun of the books that you need to find]
No Evolution: Barbaric
1st Evolution:
Classical Economics (Economy) [Ecofriendly Tree Cutting]
Serfdom (Industrial) [It's not slavery, it's work which puts them into debt]

2nd Evolution:
[Economy]
Guild (Economy, Secondary Industrial) [OPEC and Toxic Water to ward off Toxic Oil]
OR
Nationalism (Economy, Secondary Political) [Political Book on How Not to be a Liberal]
[Industrial]
Monarchy (Industrial, Secondary Political) [King Henry IIIV and 8 Wives Later Book]
OR
Tyranny (Industrial, Secondary Economy) [Napoleon's I Smell Wallpaper Poisoning Book]

3rd Evolution:
[Hybrid (ANY)]
Republic (Primary Political, Secondary Economy, Secondary Industrial) [Copy of US Constitution]
[Nationalism]
Capitalism (Primary Economy, Secondary Political, Secondary Industrial) [Get Rich Quick Book]
[Guild]
Religious Statehood (Primary Religion, Secondary Industrial, Secondary Economy) [A Book of Tree Hugging]
[Monarchy]
Empire (Industrial, Secondary Political, Secondary Expansionism)
[Caesar, 20 Stab Wounds After]
[Tyranny]
Communism (Industrial, Secondary Economy, Secondary Expansionism)
[Little Bloody Book]
Of course this suggestion isn't completely limiting tribes, it only benefits tribes more in certain areas, and tribes are free to switch with little delay. Evolution over time will allow more government types become available, and of course, the above is not a true suggestion, only an example of how a government evolution could possibly be.