Socialist thinkers stayed disengaged from working-class politics until mid-century

Evidence

Following the execution of Babeuf and his co-conspirators, it is not until almost mid-century, the years noted for the appearance of Marx and Engels, that thinkers in the socialist tradition became actively engaged in working-class politics. The historians of socialist thought take this period for what it was, in relationship to their subject, and unanimously commit themselves to exegeses. — Cedric J. Robinson, Black Marxism_ The Making of the Black…, 312