1. A method comprising: identifying event data associated with an email message; compiling, by an indexer, a real time email event from at least some of the event data; identifying a historical event representing an event that occurred at a time when the indexer was not available to determine an occurrence of the historical event in real time; responsive to a policy of prioritizing real time events over historical events, processing the real time email event before processing the historical event, the processing of the real time email event comprising: determining based at least in part on the event data that the real time email event is related to a first conversation comprising a first thread of related email messages; analyzing a time gap between the real time email event and the email messages in the first conversation; analyzing an email attachment associated with the email message to determine a topic of the email message; responsive to the time gap being less than a certain amount of time and the determined topic matching a topic of an email message in the first conversation: associating the real time email event with the first conversation; and storing the real time email event, the association with the first conversation, and the email message; and responsive to the time gap exceeding the certain amount of time: associating the real time email event with a new conversation; and storing the real time email event, the association with the new conversation, and the email message.