The imperialist policy movement gained full momentum only in the 1880s

Evidence

J. A. Hobson, Imperialism, London, 1905, 1938, p. 19: “Though, for convenience, the year 1870 has been taken as indicative of the beginning of a conscious policy of Imperialism, it will be evident that the movement did not attain its full impetus until the middle of the eighties …from about 1884.” — Hannah Arendt, The Origins of Totalitarianism, 2185

Categorization

• XREF: Dating of imperialism’s full impetus anchors the timeline of the Africa-scramble context Arendt builds around the Dreyfus Affair.