Civ 5 BNW: why are city states far tougher than major civ cities on settler?

Question

I started a game of Civ 5 BNW with the mod that makes the USA completely broken (every important unit is upgraded, start with all 4 base techs unlocked, start with 3 settlers, 3 workers and a super strong scout) to have some conquest fun (although I forgot to actually enable the conquest victory, or any victory for that matter). I didn't have any other factions on my continent (180X96 earth with true starting locations), so I could tech up in absolute peace and quiet.

So I teched up to Peacemaker (giant death robot of the US) and started conquering the other civs: Egypt, Russia, Korea, Venice and Greece. I saved Korea for last because they were the farthest away and I would have to cross the entirety of Asia to get there. I was planning on taking over all the city states on my way there, but that actually wasn't feasible. While the cities of all other factions had extremely low defense (20-30 next to their shield icon), all the city states had stats in the mid-to high 100's, like 160-180. They could go toe to toe with my peacemakers and come out on top.

Why were those city states so damn strong? Is there a hidden effect for this somewhere?

Answer 1

The defense of a city is based on its owner's Technology level and its population. While there isn't a specific bonus to city states, this does tend to make them rather well defended for several reasons.

First, there are a lot of things city states cannot build. Since they never build wonders, settlers or more than 1-2 workers, and because each city state is essentially a capital, they tend to run out of things to produce. They usually build defensive structures as soon as they become available.

Second, since city states can only expand up rather than making more cities, don't deal with unhappiness, and are founded in 4000 BC they tend to be quite large- often comparable to capitals.

These factors can often cause city states to have higher defense than most cities anyway (though this makes up for their small armies). In this case there is another factor at work- City States don't have science. Instead, their technology is based on that of other civs. Typically they have any tech that two or more civs have but they can have more if there is a runaway tech leader.

This means that while the enemy civs are multiple ages behind you (since you mentioned needing to play on settler in addition to running that mod), city-states are much closer to your level.

You're also comparing them with cities that are completely crippled by your mod and difficulty. It's actually normal for cities to have a slightly higher defense than the units they're facing- taking cities requires a lot of units.