In this age of modern hyper-sensitivity, colonialism is a topic often discussed with the lenses of negativity and exploitation. That said, in some rare instances, fate would collude and cast light in the darkness; when it comes to Cambodia, French colonialism was the one thing which kept the rich history and cultural diversity of 19th century Cambodia alive when France established the kingdom as a protectorate.
During the 19th century, the kingdom had been reduced to a vassal state, with western provinces including Angkor annexed by Siam under King Rattanakosin, while the growing Vietnamese Nguyen Dynasty threatened the eastern regions of Cambodia. Since the 1800s the Mekong River basin, had been a proxy battlefield between Vietnam and Siam (now Thailand), Vietnamese forces occupied Cambodia for several years, and when Thai forces came to the “rescue” of the Cambodians, the kingdom became a battlefield.
In full: https://www.luxuo.com/lifestyle/travel/3-days-in-siem-reap-gives-luxuo-an-experience-of-southeast-asias-rich-diversity-and-artistry.html