The credit for this turn, if credit is the right word, is generally given to the obscure writer Wilhelm Marr, whose pamphlet “The Victory of Jewdom Over Germandom Viewed from a Non-confessional Standpoint,” published in 1873, was the first to insist that, as he put it in a later work: “There must be no question here of parading religious prejudices when it is a question of race and when the difference lies in the ‘blood’.” Borrowing from the fashionable theories of the French racist Count Joseph Arthur de Gobineau, Marr contrasted Jews not with Christians but with Germans, insisting that the two were distinct races. The Jews, he declared, had gained the upper hand in the racial struggle, and were virtually running the country; no wonder, then, that honest German artisans and small businessmen were suffering. Marr went on to invent the word ‘antisemitism’ and, in 1879, to found the League of Antisemites, the world’s first organization with this word in its title. It was dedicated, as he said, to reducing the Jewish influence on German life.
(The irony of all this is that Marr’s “second wife, who was Jewish, supported him financially until her death in 1874 . . . “)
— from Richard J. Evans’ massive (and fascinating) The Coming of the Third Reich