The earliest release date script is a basic Mediamonkey script that will populate the original date field in the MM database as well as the song tags. There are other options to use the date field instead, use day and month if available, to search by selection or now playing, to automatically update with no user intervention, and so much more. See the MM forum discussion for more details.
Many compilation, best of, remastered, and sountrack albums are released many years after the songs were first recorded. Most taggers will find the year these album types were first released but what you really want is the date the songs were first released.
Singles can also be released many months or years before they appear on an album. Is the original release date important to you?
The script queries the Discogs or Musicbrainz API's to find the earliest date a song has been released based on the song title and artist name in the Mediamonkey database.
Get the latest script here