Final answer:
During the 1940s to 1950s, African nationalism evolved significantly, characterized by political actions for self-rule and anticolonial movements impressed by Pan-Africanism and influential figures like W. E. B. Du Bois, culminated in independence movements such as the Mau Mau Revolution.
Step-by-step explanation:
The Changing Nature of African Nationalism
The period of the 1940s to the 1950s marked a significant era in the evolution of African nationalism. Fired by the aspirations of self-determination and independence enclosed within Alfred Xuma's 'African Claims', African nationalists sought to reclaim their rights and governance from colonial powers. Driven by the inspirational works of figures like W. E. B. Du Bois and the rise of Pan-Africanism, African nationalists agitated for change both through political pressure and anticolonial struggles.
The spirit of this movement spread across the continent, evident in the actions of entities such as the National Congress of British West Africa, which aimed at integrating elected assemblies into the governance of West African colonies. Similarly, the Malagasy Revolt in Madagascar and the fight for independence in Algeria underscored the growing urgency and militancy in these nationalist movements. Marcus Garvey's universalist approach to uniting people of African descent and the Mau Mau Revolution in Kenya, a prolonged anticolonial struggle that eventually won independence from Britain, indicated the tangible actions taken to realize the aspirations of African nationalism up to 1955.
These developments were further supported by cultural movements and scholarship emphasizing the importance of Africa's role in world history, as seen in the African-centric artworks acknowledged at the Metropolitan Museum of Art's show 'The African Origin of Civilization', which drew from both Ancient Egyptian and Sub-Saharan African connections.