Full Idea
The rejection of idealism by Moore and Russell was marked in 1898 by the publication of Moore's article 'The Nature of Judgement'.
Gist of Idea
Moore's 'The Nature of Judgement' (1898) marked the rejection (with Russell) of idealism
Source
report of G.E. Moore (The Nature of Judgement [1899]) by A.C. Grayling - Russell Ch.2
Book Reference
Grayling,A.C.: 'Russell' [OUP 1996], p.26
A Reaction
This now looks like a huge landmark in the history of British philosophy.