Marx's theories are deeply historical, in that he wants to explain the dynamics of change of large historical formations such as capitalism or feudalism, and he insists on putting social events into historical context. And, of course, Marx is most celebrated for developing a general approach to historical explanation, the theory of historical materialism. But how does Marx do when he treats concrete historical events? How is Marx as an historian?
There are surprisingly few extended examples of detailed historical analysis in Marx's writings. There is Marx's account of "primitive accumulation" in English agrarian history in the 17th and 18th centuries in Capital. There are occasional references to the Roman Empire and classical slavery throughout his work. And there are his important writings about the French urban uprisings during 1848 and its aftermath (The Eighteenth Brumaire and The Civil War in France). These essays include quite a bit of historical detail -- personalities, events, parties, speeches. But they are closer to political journalism than to careful historical analysis. They are based primarily upon Marx's personal contemporary observations -- not on the usual historian's studies in archives and secondary sources. They come closer to personal recollections and observations than to a typical historical research product.
If there is a unifying theme of interpretation in these articles, it is the idea that the parties and factions pursue programs that are based on class interests. The party of order defends property and privilege, and the party of progress expresses and defends the interests of the underclasses -- urban workers and artisans. Theorists such as Nicos Poulantzas have used these texts as a basis for propounding theories of political consciousness and action and the "relative autonomy" of politics. The essays illustrate Marxist theories of politics. But considered solely from the point of view of historiography and historical knowledge, the articles aren't particularly distinguished.
Let's make an unfair but informative contrast: a comparison between Marx's writings and those of some of the great twentieth-century historians whom his ideas inspired. I'm thinking of scholars like Albert Soboul, Eric Hobsbawm, E. P. Thompson, Maurice Dobb, or Gene Genovese. Each of these scholars borrowed deeply from Marx's social theories -- class, power, consciousness, resistance, economic structure, property systems, labor. But each of these historians does something else as well: he digs deeply into the gnarly, special, and resistant reality of historical events and groups -- peasant movements, churches and manifestoes, parties and conspiracies, slave quarters. These historians try to discover the particular and peculiar graininess of history; they allow theory to rest lightly on their narratives.
So what does Marx have to teach us about the craft of historical writing and reasoning? I'm inclined to say that Marx uses history but doesn't really write history. His writings are historically oriented, but they are almost never works of primary historical discovery and explanation. Marx is a theorist of historical processes; but he is not really a working historian, and his writings don't really offer much by way of innovative historical reasoning. It remained for Marxist historians of the twentieth century to bring together Marx's theoretical insights with rigorous methods of historical research and discovery.