The Kremlings are crocodilian enemies appearing in many of the Donkey Kong games, first being Donkey Kong Country. The Kremlings altogether are known as the Kremling Krew. They all are mainly located in Crocodile Isle. The Kremlings, however, did make a few appearances in the Mario series such as a Kritter being a goalie in Mario Strikers Charged and Super Mario Strikers along with being a playable character in Mario Super Sluggers. Klaptraps appear in Donkey Kong's Jungle in the game Mario Superstar Baseball. Kremlings are known to come in a variety of colors, mainly green.
Several evidences by whole Crocodile Isle which the Kremling population was primitive race where lived in Lost World, but they began to multiply by infesting the whole island. The Kremlantis it is further evidence that more Kremlings built their civilization to this island become submerged.
In wrecked ships and undead Kremlings with pirate clothing as Kloak, Kackle and Krossbones; is possible that the Kremlings formed their pirate society as Kremling Kuthroats where valute objects are stored in own island and ships which is wrecked.
Shown in shield from Krocodile Kore and Kremkoins, it's very likely King K. Rool served as chosen to command this race inaugurating the Kremling Krew. He played an important role in creation of monarchy in own island, but abuse of power from same corrupted their society turned them into a thoughened race (mentioned by K. Lumsy) and treated poorly (mentioned by Klubba). The same abuse of power which wasted all resources from own homeworld, polluters due to industrial bases and advanced by its technology.
They were even taught by Wrinkly Kong when she founded her private school in Crocodile Isle. Already show lousy at math exam and one was punished for being with a sword in class. But their chances of being educated were lost when the school was sunk in the ocean with the whole island.