Cities are objects on the map that produce stars and let you train units. Cities are acquired from capturing villages. When you level up a city, your resource production goes up by 1 (or 2 if you choose Workshop when upgrading to level 2).
City Levels Edit
|Lvl 1||Lvl 2||Lvl 3||Lvl 4||Lvl n|
|Population needed to upgrade||2||3||4||5||n+1|
|Earned points when built||100||40||35||30||n-5|
|Star produced (without Workshop)||2||3||4||5||n+1|
|Choose between reward #1||-||Workshop||City wall||Population growth||Park|
|or between reward #2||-||Explorer||Resources||Border growth||Super Unit|
Your Capital is your starting city. Capitals produce by default 1 more star per turn than other cities when it's that tribes' capital. You can connect other cities to your capital with roads and ports. Each capital contains a prism specific to each tribe.
Your territory is the land you own. You can only construct buildings in this area (with the exception of Roads, which can be built in unclaimed territory as well). In contrast, you may only build units in the city tile itself. Your territory is marked by a dashed line with the color of your tribe. You can expand your territory by upgrading your city to level 4, where you can choose to increase your population or expand your borders.
A red bar below your city, explained in Population.