Immanuel Wallerstein was a prominent sociologist known for his influential work in the field of world-systems analysis. He was born in New York City on September 28th, 1930, and his academic journey began at Columbia University under the mentorship of Robert Merton. Early in his career, Wallerstein was deeply influenced by the system thinking of Talcott Parsons.

From 1958 to 1971, he served as a professor at Columbia University and became an expert in African studies. He was a vocal advocate against colonialism during this period. In 1968, amidst the student revolts in the United States, Wallerstein authored a book on the university student uprising. Following his tenure at Columbia, from 1971 to 1976, Wallerstein held the position of a sociology professor at McGill University in Montreal, Canada. This period marked his transition into a more global perspective. In 1976, he moved to Binghamton University, State University of New York, where he remained until 1999.

He also assumed the role of the head of the Fernand Braudel Center for the Study of Economies, Historical Systems, and Civilizations, a position he held until 2005. It was during this time that Wallerstein gained worldwide recognition, particularly after the publication of the first volume of his seminal work, "The Modern World-System" in 1974.

In addition to his teaching and administrative roles, Wallerstein was a tireless school reformer. He transformed the Fernand Braudel Center into a renowned research institution with its own journal, "Review." He also served as the president of the international sociological association from 1994 to 1998. From 2000 onward, Wallerstein continued his scholarly pursuits as a Senior Research Scholar at Yale University's sociological institute.

Wallerstein's significant contributions to the field of sociology include works such as "The Modern World-System" series, "The Capitalist World-Economy," "The Decline of American Power," and "World-Systems Analysis: An Introduction."

His central theory revolved around the concept of world-systems, where he categorized regions into core, semi-periphery, and periphery based on their economic roles. Wallerstein argued that the wealth of core regions depended on exploiting the resources and labor of peripheral regions, a dynamic that persisted despite decolonization.

He emphasized the importance of analyzing social systems at a broader level than the nation-state and criticized conventional notions of society and culture as being too closely tied to national borders. Wallerstein's work was marked by its focus on endogenous explanations for social change within these world-systems.

Wallerstein's work has not been without criticism. Some have found his system theory to be overly abstract and economically deterministic, neglecting cultural, political, and individual factors. Critics also argue that he paid insufficient attention to the role of politics, military conflicts, and the significance of democracy in shaping the world-system.