There are also a ton of other ethnic groups in China and the government just call them all Han Chinese. Tons of ethnic groups in Russia too. These are countries

There are also a ton of other ethnic groups in China and the government just call them all Han Chinese. Tons of ethnic groups in Russia too. These are countries with very long histories that span a large area, with many areas that were multiple kingdoms, tribes, etc. Makes perfect sense that they would have a lot of different ethnic groups.