Not to discourage further replies, but a while back I wrote an answer to this question in reference particularly to the ancient Romans, who already commonly used locks and keys: https://www.reddit.com/r/AskHistorians/comments/7aloob/did_people_in_antiquity_have_keys_for_their_homes/dpbxc9z/

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You know how it goes. This thread is trending high right now and getting a lot of attention, but those upvotes represent interest in the question, and it can often take time for a good answer to be written. The mission of /r/AskHistorians is to provide users with in-depth and comprehensive responses, and our rules are intended to facilitate that purpose. We remove comments which don't follow them for reasons including unfounded speculation, shallowness, and of course, inaccuracy.

Making comments asking about the removed comments simply compounds this issue. So please, before you try your hand at posting, check out the rules to see if you have the right key for this lock, as we don't want you to trigger the alarm.

While we always appreciate feedback, it is unfair to the OP to further derail this thread with META conversation, so if anyone has further questions or concerns, I would ask that they be directed to modmail, or a META thread. Thank you!