Here is a small section I wrote about each of the kingdoms, I tried to make them seem equal...
Samurai
As swift as the wind these silent midnight stalkers swifly run through the battlefeild, killing all who cross their path.
Leader: ???
Food of Choice: Sushi
Weapon(s) of Choice: Naginata, Ninja Swords(Katanas and Tachis)
Rescource of Choice: Bamboo
Job(s): Farming, Fishing
Dustari
Using utter force these noble warriors pound down any enemy that dares stand up against them. With powerful swords and armor they are tough to defeat.
Leader: Kamuii Nightrose?
Food of Choice: ???
Weapon(s) of Choice: Broad Swords
Rescource of Choice: Metal
Job(s): Mining, Crafting
Zormite
With the power of aquatics at their disposal, this group of fish-like people race through the ripling waves to attack enemy kingdoms from the sea.
Leader: ???
Food of Choice: Anything other than fish
Weapon(s) of Choice: Water
Rescource of Choice: Ice
Job(s): ???
Forest
Amongst the trees these forestfolk dwell. With plantlife around them to use in battle they can make their foes fall.
Leader: ???
Food of Choice: ???
Weapon(s) of Choice: The Plants
Rescource of Choice: Wood
Job(s): Farming
Pirates
With great ships of timber these ocean warlords sail the sea killing anything in their paths with their mighty cannons ablaze.
Leader: ???
Food of Choice: Fish, Meat
Weapon(s) of Choice: Daggers, Cannons
Rescource of Choice: Wood
Job(s): Fishing, Hunting