1. A method comprising: identifying, by a computing device, a plurality of email subjects in an email corpus stored on a storage device; performing on each computing node of a plurality of nodes, each of said nodes including one or more processors coupled to a memory: retrieving a given email subject from the plurality of email subjects, wherein the given email subject is only retrieved by a single node; identifying a plurality of emails which are associated with the given email subject; storing, on the node, a plurality of emails associated with the given email subject; and reconstructing one or more email threads from the plurality of emails by determining relationships between the plurality of emails based at least in part on: header information responsive to determining the header information is in a given format; and content of the plurality of emails responsive to determining the header information is not in the given format; and conveying the reconstructed one or more email threads to a database for storage.