Email activities are tied to the associated email address and not a specific contact record. Hence, email activities can occur on a date prior to a contact's Create Date. Likely scenarios for this include:
- A contact was previously sent emails. The record was deleted from your contact database and then was re-created.
- A contact record originally had one email address and that email address was changed. A new contact record was then created with that original email address of the first contact. Any email activities tied to the original email address on the first contact record will now appear on the new contact record.