the penguin classics edition of The Communist Manifesto is very well worth it for the preface alone

author seems anti-Communist but i still find [their] history of the ideas leading up to the Manifesto useful, even if only really for its own sake

@aescling my university recommended Karl Marx: Selected Writings ed. Lawrence H. Simon pub. Hackett, which begins with the sentences « Karl Marx is the most influential thinker of the modern period. Indeed, one could go further and claim that, in terms of sheer numbers, Marx’s ideas have had a greater impact on more people than those of anyone else in history, with Jesus, Buddha, and Muhammad his closest rivals. »