Sun Yat-sen's thought of "expelling Tatars and restoring China" refers to overthrowing the aristocratic rule of the Qing Dynasty and restoring the political power to the Han people. Here, China can refer to the Han nationality or the political power established by the Han nationality. This is the concrete explanation of nationalism in the Three People's Principles.
"China" first refers to the "center of the world", that is, the Heluo area in the middle and lower reaches of the Yellow River, and then gradually contains the orthodox meaning of dynasty rule. After the founding of the Republic of China, "China" officially became the modern title of the Chinese nation.