The African nationalist movement was a group of people who wanted to make Africa a better place for Africans. They believed that Africa had been controlled and oppressed by other countries and wanted Africans to have more control over their own lives.
Just like how you might like to control what you eat for breakfast, Africans wanted to control their own countries and make their own decisions about how things would be run.
They met and talked with other Africans who also shared their beliefs and ideas about how to change things. They protested and demanded changes from the governments that were running their countries.
Sometimes they were peaceful, but other times they had to fight back against the people who were oppressing them. They wanted to make Africa a place where everyone could live freely and peacefully.
This movement was important because it helped many African countries gain independence from the countries that had been controlling them. It also helped create a sense of pride and unity among Africans, who were finally able to take control of their own destinies.