[3] He was a Senior Research Scholar at Yale University from 2000 until his death in 2019, and published bimonthly syndicated commentaries through Agence Global on world affairs from October 1998 to July 2019.

[8] He received all three of his degrees from Columbia University: a BA in 1951, an MA in 1954, and a PhD in 1959, where he completed his dissertation under the supervision of Hans L. Zetterberg and Robert Staughton Lynd.

[11] Originally, Wallerstein's principal sub-area of study was not American affairs, but the politics of the non-European world, specifically India and Africa.

[8] For two decades Wallerstein researched Africa, publishing numerous books and articles,[8] and in 1973 he became president of the African Studies Association.

[15] The Center opened with the publishing support of a new journal, Review,[9] (of which Wallerstein was the founding editor), and produced a body of work that "went a long way toward invigorating sociology and its sister disciplines, especially history and political-economy".

[23] Wallerstein began as an expert on post-colonial African affairs, which he selected as the focus of his studies after attending international youth conferences in 1951 and 1952.

[24] His publications focused almost exclusively on this topic until the early 1970s, when he began to distinguish himself as a historian and theorist of the global capitalist economy on a macroscopic level.

"[8] In The Essential Wallerstein, he stated that: "Fanon represented for me the expression of the insistence by those disenfranchised by the modern world‑system that they have a voice, a vision, and a claim not merely to justice but to intellectual valuation.

";[8] that Braudel, for his description of the development and political implications of extensive networks of economic exchange in the European world between 1400 and 1800, "more than anyone else made me conscious of the central importance of the social construction of time and space and its impact on our analyses.

Wallerstein's first volume on world-systems theory (The Modern World System, 1974) was predominantly written during a year at the Center for Advanced Study in the Behavioral Sciences (now affiliated with Stanford University).

An initially slight advance in capital accumulation in Britain, the Dutch Republic, and France, due to specific political circumstances at the end of the period of feudalism, set in motion a process of gradual expansion.

Contrary to affirmative theories of modernization and capitalism, Wallerstein did not conceive of these differences as mere residues or irregularities that can and will be overcome as the system evolves.

Natural resources, land, labor, and human relationships are gradually being stripped of their "intrinsic" value and turned into commodities in a market which determines their exchange value.

[citation needed] In the last two decades of his life, Wallerstein increasingly focused on the intellectual foundations of the modern world-system and the pursuit of universal theories of human behavior.

In addition, he showed interest in the "structures of knowledge" defined by the disciplinary division between sociology, anthropology, political science, economics, and the humanities, which he himself regarded as Eurocentric.

[citation needed] Wallerstein's theory provoked harsh criticism, not only from neo-liberal or conservative circles but even from some historians who say that some of his assertions may be historically incorrect.

Nevertheless, his analytical approach, along with that of associated theorists such as Andre Gunder Frank, Terence Hopkins, Samir Amin, Christopher Chase-Dunn, Thomas D. Hall, Aníbal Quijano and Giovanni Arrighi, has made a significant impact on the field and has established an institutional base devoted to the general approach of intellectual inquiry.

Arthur Stinchcombe was very critical of Wallerstein's The Modern World-System, writing that the book presents no theoretical argument and no determinate mechanisms.

Stinchcombe also argues that the book does not define its concepts independently of their effects, thus entailing tautologies regarding cores, peripheries and semi-peripheries.

The main characteristic of his definition is the development of a global division of labour, including the existence of independent political units (in this case, states) at the same time.

[citation needed] According to him, global conflicts occur as the summer phase of a wave begins, which is when production of goods and services around the world are on an upswing.