Hello WillK,
"Activation Lock for iPhone, iPad, and iPod touch" is a security feature with an added aspect of possibly deterring re-selling of stolen devices. To learn more click here --> http://support.apple.com/HT201365
For an individual to remove an activation lock this absolutely requires the information for the account that applied the lock. Click on this link to learn 'How to remove Activation Lock' --> https://support.apple.com/HT201441
If you do not know the required information and you are not the original owner, get the owner of the account to remove the lock or return the device for a refund or recycle it. The device is otherwise useless to you. Eric Root has pretty much summed it up.
One other option is a long shot and that would be for the owner to try using this service: Apple can completely reset a device if a person can provide sufficient evidence of valid ownership. Do this online at: Activation Lock support request - https://al-support.apple.com/#/additional-support Apple says, "Proof of ownership documentation is required," but does not state what currently constitutes proof. Prior to this new online service Apple typically required the original receipt issued by an Apple Authorized dealer and documented provenance (so typically it would be the original owner who does this, or a descendant with legal proof of ownership).