By following the policy of Imperilism.
The superiority of Martial Power: The Westerners had armed technological advancement that was more exceptional than armories of all of the Muslim Countries.
As a consequence, they were able to annihilate any command sent to command their colonial soldiers.
Agreements with Regional Rulers: Various Colonists, the British particularly, favored to leave the captured Muslim Empires in command of their regions since they previously had various representatives and executives on the regional levels in the several territories.
Assurance of Minority community: Hebrews, Catholics, and other spiritual oppositions were in a frightening situation in the Muslim World before overseas arrival, where they were required to meet additional expenses and inadequate to play a significant role in administrative affairs. In the territorial system, all domestic residents were considered equal.