Hello,
By default, you can access past events by going to yoursite.com/events/past (or yoursite.com/missions/past since it looks like you changed your events slug).
You can also display past events by setting the “date” parameter in the tribe_events shortcode to the date (in the past) from which you would like to display events.
If this doesn’t get you what you’re looking for, can you please provide some more details on where you would like to include past events?
Thanks,
Jennifer