I don't know which specific context you refer to - the Han Chinese have conquered many people.
So I will provide one example - in Taiwan, the aboriginal people were required to have Chinese names in their passports until recently, which means that every person was forced to adopt a Chinese name, and often their original name was dropped, and (over generation) forgotten. This has changed how people self-identify: weakening their indigenous sense of identity.
Well you could say Cuba had a dictatorship
One of the actions that were done to promote assimilation among American Indians, both in the US and in Canada, but also for example in Denmark, is compulsory sending them to boarding schools.
In those schools, the children were forbidden to speak their indigenous language, and many came home (if they were allowed to come home) without being able to communicate with their parents.
One of the best known battles representing a native american victory during the indian wars was Little Big Horn, in which colonel Custer was killed together with almost three hundred men. Custer was leading a force of about seven hundred soldiers, but a combined force of Dakota, Lakota and Chetenne warriors prevailed.
