French authorities controlled their colonial territories in Indochina through a combination of military force, administrative systems, and cultural assimilation. They established a centralized colonial administration that imposed French law and governance over the local populations. French military presence was significant, suppressing any resistance and maintaining control over the territories. They also implemented policies that favored French economic interests, exploiting the region's resources and labor for the benefit of France. Additionally, the French authorities promoted the spread of French culture and language, attempting to assimilate the local population into French ways of life. These measures allowed France to maintain its colonial dominance in Indochina until the mid-20th century.
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~~~Harsha~~~