First published in 1886 in Die Neue Zeit. It was intended to rebut a resurgence of neo-Idealism in German ruling class circles. It was reprinted in Stuttgart two years later, with some changes made by Engels.
Engels considered this something of a summation or closure of the post-Hegelian criticism Marx and he had initiated in The German Ideology 43 years before -- which work was never published in their lifetimes.