The end of colonization corresponded to the hope for a new morrow. In this respect, colonialism which led to the occupation of African territories and the downfall of African traditional culture drastically caused the erosion of African traditional ways of life. To solve this, the Kenyan writer Ngugi wa THIONG’O made a firm decision to revalorize his African traditional culture and values by writing most of his works in Gikuyu in order to end linguistic imperialism. This Kenyan scholar strives to decolonize the minds of millions of Africans who continue to promote the legacy of colonialism by writing and publishing in foreign languages. This work tends to demonstrate Ngugi’s conception of language issue and how the recognition of national languages participates to the downfall of Western culture and the promotion of African national languages especially Gikuyu. This study also allows us to understand the role played by local languages to strengthening African cultural identity and values.