Colonial regimes have frequently shown a preference for sharing the burdens of defence with certain ethnic groups of the countries under their control. The advantages of a policy of this type—the essence of the divide and rule system—were many and varied. Binding natives to the service of colonial defence solved the functional problems of manpower in situations where no adequate corps of white regulars was readily available. The practice was cheaper to maintain and found to be an effective instrument of control. Its employment also drew off warlike elements that might have made trouble.