The title of this paper might suggest that it is intended to describe Chaadayev's philosophy. This is not so. An attempt will be made, rather, to argue the following points: first, that Chaadayev is chronologically the first philosopher of Russia because earlier persons to whom that distinction has been attributed do not really deserve it; second, that, unlike these so-called predecessors, Chaadayev in his writings provides a body of material which qualifies as a philosophy and which is presented as such; and third, that his philosophy is distinctively Russian, even though Chaadayev combines many Western philosophical characteristics with his native Russian outlook.