An anarcho-syndicalist writer and activist of some prominence, whose politics had a major influence in the Spanish Civil War and the jewish émigré community in London, England (see The London Years). His political ideas had emerged from the failings of late 19th century Marxism/Social Democracy under the Germany's SPD, having seen firsthand the erosive influence of electoralism.
Would maintain lifelong relationships with Emma Goldman and Errico Malatesta among others.
For more, including e-texts of his works:
http://libcom.org/tags/rudolf-rocker