When a list is deleted, Campaigns that were sent to the deleted List will also be removed from the platform.
However, if the Campaign was sent to more than one list at the time of the send, and those lists are still intact, the campaign will not be deleted.
We do not recommend deleting lists. This is because you will permanently lose all data associated with that list. This includes reports, campaigns, campaign statistics, settings (segments, fields, etc), and any contacts that you are not adding to the destination list. This action cannot be undone. We are unable to restore deleted campaigns.