What does the following sentence mean: "in direct rule sowed the seeds for class and ethnic tensions"?

Indirect rule is a type of government in which existing political elites and institutions continue to rule in a country. 
The sentence, 'Indirect rule sowed the seeds for class and ethic tension' means that, indirect rule was the root cause, the principal reason why class and ethnic tensions occurred. The indirect rule was the factor that brings about class and ethnic tension.