In addition to his work as a dramatist and poet, Césaire was a philosopher and a theorist, whose work perhaps most notably included creating the theoretical concept of "Négritude," which he developed in collaboration with the first President of Senegal, Léopold Sédar Senghor, and the French Guianan thinker and politician Léon Damas. "Négritude" is a critical and literary framework that centers the Pan-African identity and employs Marxist political philosophy as well as Black radical philosophy to empower black subjects of colonialism. It countered colonial logics that sought to assimilate black people into dominant social structures, and instead opens space for African culture to recognize its own integrity, as well as reject Western domination.
Césaire, Senghor, and Damas were disheartened by their experiences as Afro-French individuals in France and wanted to resist the racism as well as the systemic inequality within the French educational system. More specifically, Césaire was disheartened by Caribbean and Afro-French individuals who looked down on their own African origins as savage and uncivilized. With the concept of "Négritude," he hoped to give black people tools to celebrate their own African identity, rather than strive to leave it behind in hopes of fitting in with European social systems.
In a 1967 interview with the Haitian militant and poet Rene Depestre, Césaire said of Négritude, "There has been too much theorizing about Negritude. I have tried not to overdo it, out of a sense of modesty. But if someone asks me what my conception of Negritude is, I answer that above all it is a concrete rather than an abstract coming to consciousness. What I have been telling you about—the atmosphere in which we lived, an atmosphere of assimilation in which Negro people were ashamed of themselves—has great importance. We lived in an atmosphere of rejection, and we developed an inferiority complex. I have always thought that the black man was searching for his identity. And it has seemed to me that if what we want is to establish this identity, then we must have a concrete consciousness of what we are—that is, of the first fact of our lives: that we are black; that we were black and have a history, a history that contains certain cultural elements of great value; and that Negroes were not, as you put it, born yesterday, because there have been beautiful and important black civilizations. At the time we began to write people could write a history of world civilization without devoting a single chapter to Africa, as if Africa had made no contributions to the world. Therefore we affirmed that we were Negroes and that we were proud of it, and that we thought that Africa was not some sort of blank page in the history of humanity; in sum, we asserted that our Negro heritage was worthy of respect, and that this heritage was not relegated to the past, that its values were values that could still make an important contribution to the world."
