When I look at the civs in AoE2, I think we already could split this game in two, one covering the Late Antiquity and Early Middle Ages (with Goths, Huns, late Romans together with Byzantines, early Franks throwing axes around, all Slavs grouped together, Vikings, Saxon, etc.) and the other one covering the High and Late Middle Ages and the Renaissance (with French, Spanish, English, German, Portuguese, Italian, Russians, Poles, Mongols, Turks, gunpowder, etc.)
Some of AoE2 civs are clearly designed with one of those eras in mind, either because they didn’t exist in the other half of the Middle Ages, because the game designers couldn’t decide which part of their history they were more intersted in (this one is especially true for the Franks who were there during the whole time period but get access to their unique unit at the exact age where they should stop using it and change their name)
Now, having an even larger timeframe as I’ve heard we were told about doesn’t only mean more historical inaccuracy and less consistancy, it would also result in way more civs never appearing in any AoE game. The game designers have way more options to chose from, but not more time and resources to work on them all, and I’m a little bit worried by the number of intersting factions which will get the axe.
Yeah I´ve read the same and have the same worries. AoE2 already covers like 400 AD (I mean if you have Goths that can´t even build stonewalls) to the Turks with Gunners (15th century) which actually does not belong to medieval anymore… frustrating confusion here. 3 Ages should be enough actually, you would not lose a lot of fun factor. But seems to be 4 ages again.
I´ve heard the speed of different civs climbing up the ages will be supposed to be different too. So I am wondering if there are different costs in age ups. Since Mongols are known to be waiting in the wings, we might have the same unrealistic scenario of mounted horseman chargin into cannon fire again. 
And I heard the basic units will be completely different from civ to civ so there won´t be like Knights available for everyone which is nice.
We see a lot of British buildings in the trailer with Jacobean era architecture and chimneys, so I assume the game goes into the early 17th century at least, if not late 17th at most. Compare this to this.
cover large time period would just be another empire earth? or rise of nation?
I know this is several months old but
That is not unrealistic at all, cavalry charges into cannon fire continued to exist and were actually fairly effective until halfway into WW1 - still equipped with lances or sabers, it only fell off when entrenched positions with machineguns became common and the tank was invented
I guess it is from the late Renaissance era to World War I.
I’m afraid that having a bigger time frame makes the game feel more wrong.
Like a late antiquity army should have no chance against an early modern army with Arquebus and Pike formations supported by early field guns.
Why would you think that? Middle Ages are already confirmed. The game will end with the Renaissance, that was confirmed in interviews.
This overlaps with the AGE2 era,Why they do this
Because AoE2 is the most popular.
AoE2 and it’s engine is also over 20 years old by now so starting from there is the most logical thing.
In this way, AGE 2 users will be divided, and the most logical business strategy for AGE 4 should be new themes to attract new players…
I think after more than 20 years it’s possible to make a game in the same setting again.
Half of the AoE4 players will probably be people that weren’t even borne when AoE2 come out.
A larger time period is okay with me, mainly if they mostly go backwards in time rather than forwards to make it larger