However, despite Bismarck's initial scepticism, the foundations of the German colonial empire were already laid during his tenure from 1884 onwards, when the government began to place the privately acquired properties of colonisers like Adolf Lüderitz, Adolph Woermann, Carl Peters and Clemens Denhardt under the protection of the German Reich, necessitating costly action such as in the 1888 Abushiri revolt. According to the German historian Hans-Ulrich Wehler, German colonial policy in the 1880s was an example of a "pragmatic" social imperialism, a device that allowed the government to distract public attention from domestic problems and preserve the existing social and political order.