How has the political map of the world changed in the 19th century? What events were at the heart of this process?

By the beginning of the 20th century, there were 61 independent states in the world, but most of the planet was divided among several states.
It was based on great geographical discoveries.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.