Head of the "Youngest Historical School," he was one of the leading Continental European social scientists during the first quarter of the 20th century.

In 1888, he received his Ph.D. from Berlin under the direction of Gustav von Schmoller and Adolph Wagner, then the most eminent German economists.

[citation needed] As an economist and especially as a social activist, Sombart was then seen as radically left-wing, and so only received — after some practical work as head lawyer of the Bremen Chamber of Commerce — a junior professorship at the out-of-the-way University of Breslau.

Sombart, at that time, was an important Marxian, someone who used and interpreted Karl Marx — to the point that Friedrich Engels said he was the only German professor who understood Das Kapital.

Sombart called himself a "convinced Marxist,"[2] but later wrote that "It had to be admitted in the end that Marx had made mistakes on many points of importance.

[citation needed] Sombart was not the first sociologist to devote an entire book to the concept of social movement as he did in his Sozialismus und soziale Bewegung, published in 1896.

[citation needed] Sombart's magnum opus, Der moderne Kapitalismus (Historisch-systematische Darstellung des gesamteuropäischen Wirtschaftslebens von seinen Anfängen bis zur Gegenwart)[4] is a systematic history of economics and economic development through the centuries and very much a work of the Historical School.

"[9] In 1903, Sombart accepted a position as associate editor of the Archiv für Sozialwissenschaft und Sozialpolitik, where he worked with his colleagues Edgar Jaffé and Max Weber.

Here, inter alia, companion volumes to Modern Capitalism dealing with luxury, fashion, and war as economic paradigms appeared; the former two were the key works on the subject until now.

He argued that Jewish traders and manufacturers, excluded from the guilds, developed a distinctive antipathy to the fundamentals of medieval commerce, which they saw as primitive and unprogressive: the desire for 'just' (and fixed) wages and prices; for an equitable system in which shares of the market were agreed and unchanging; profits and livelihoods modest but guaranteed; and limits placed on production.

Excluded from the system, Sombart argued, the Jews broke it up and replaced it with modern capitalism, in which competition was unlimited and the only law was pleasing the customer.

[11] Paul Johnson, who considers the work "a remarkable book", notes that Sombart left out some inconvenient truths, and ignored the powerful mystical elements of Judaism.

Sombart refused to recognize, as Weber did, that wherever these religious systems, including Judaism, were at their most powerful and authoritarian, commerce did not flourish.

Jewish businessmen, like Calvinist ones, tended to operate most successfully when they had left their traditional religious environment and moved on to fresher pastures.

[12] In his somewhat eclectic 1913 book Der Bourgeois (translated as The quintessence of capitalism), Sombart endeavoured to provide a psychological and sociological portrait of the modern businessman, and to explain the origins of the capitalist spirit.

[15] German socialism must effect a "total ordering of life" with a "planned economy in accordance with state regulations".