Final answer:
European colonial powers such as France and Britain colonized Southeast Asia, exploiting the local population for labor and resources and introducing diseases. Colonialism also altered the social structure, introduced new religions, and influenced trade relationships and borders.
Step-by-step explanation:
Colonialism had a significant impact on the lives of people in Southeast Asia. European colonial powers such as France and Britain colonized the mainland region of Southeast Asia, while Siam (now Thailand) remained independent. The colonizers exploited the local population for labor, forced them to grow cash crops, and introduced diseases that caused widespread illness and death. Additionally, colonialism altered the social structure, introduced new religions, and influenced trade relationships and borders.