Kamino is a water-covered planet located in Wild Space in the Star Wars galaxy. Home to the Kaminoan race, it is the planet that produced the first batch of clones that would become the Grand Army of the Republic.
Creating the Clone Army
The original order placed for the clone army was at the request of Jedi Master Sifo-Dyas, in 32 BBY. The clone army would have probably been known to the rest of the galaxy, had Count Dooku not killed him.
Kamino was attack twice during the Clone Wars, the first attack occuring two months after the Battle of Geonosis, and the second attack occuring 31 months after the Battle of Geonosis. Both battles ended in Republic victories.
During the rule of the Galactic Empire, Kamino was under careful observation by the Emperor, making sure that the cloning capabilities of the planet would stay under Imperial control. This predictably upset some of the Kaminoans, leading to the creation of a small batch of "anti-trooper" clones -- clone soldiers brought up specifically to fight the Empire. An Imperial force, led by Boba Fett, was tasked to suppress this uprising and bring the cloning facilities under Imperial rule.
After the battle, which ended in an Imperial victory, the Emperor decided to diversify the Stormtrooper ranks, using different clone templates and even birth born soldiers.