The Kzin homeworld is called "Kzin" by all other races save the Kzinti, who call it "Homeworld" or "Kzinhome". It orbits the star 61 Ursae Majoris, has stronger surface gravity and both a longer day and year than Earth. Central planet of the Kzinti Empire, the Patriarchy.
The Patriarch rules from a large palace on the world. At the end of the last Man-Kzin War, around 2618, Kzin was occupied and disarmed by human armies.