In the year 3000 BCE, the Borg began their campaign to assimilate all life forms in the universe. Their first major conquest was the planet Earth, where they assimilated the human race and created the Borg Collective.
The Borg's hierarchy was simple: Queen to Drone. The Queen, a being of immense power and cunning, held absolute control over the Collective.
Below her were the Drones, the foot soldiers of the Borg. These were the ones who fought and died for the Queen, their individuality erased in the process.