Reddit mentions of Russian Philosophy V2: Nihilists, Populists

I'm glad it was useful! I've spent a long time following internet rabbit holes and searching dusty library corners for these folks, so I'm glad to pass it along. There are, regrettably, not very many books collecting all these fascinating figures, but I know of a couple. Copleston's famous history of philosophy includes a volume on them. There's a several volume set which serves as kind of an anthology of writings from a variety of schools in that period (here's the link to the second volume, which contains stuff on nihilism and populism). There's also a good biography in English on Pavel Florensky, which digs a bit into the details of this time (and Florensky is worth taking the time to read--just ask /u/blazingtruth).

A few of the Russians who made it to Paris wrote their own surveys, histories, and reflections, but they are of course quite biased (most of these guys are from the Solovyov strand, though, so you'll get a lot of good stuff on his lineage). On this, see Berdyaev's The Russian Idea, Dream and Reality (which is his autobiography), Lossky's History of Russian Philosophy, and others.

As for Solovyov's stuff, Eerdmans publishing has been putting out some of his material in English over the years (they've also translated Bulgakov's works). I know of only two in print right now (find them here). I've read the book on the Good which is nice because you don't have to commit from start to finish--you can sort of skip around--and it introduces Solovyov's metaphysics and his social thought. The second half of it is more practical application of his philosophy/theology.

As you can see, the field is a bit sparse in terms of secondary engagement. You can find articles here and there if you have access to library databases. For anyone looking for research interests or grad school work, learning Russian could be a ticket to a niche area of reading and thinking (it's one I'm thinking of pursuing in Ph.D. work).