I ask because I've been watching a few dramas set in historical settings and particularly in the ancient world, there's no locks. Seems like theft would have been a massive problem, especially in large cities like Rome.
Also, apologies if this falls foul of the "no first/last" rule. I thought that since I was asking about them being prevalent, it would be acceptable.
More can be written, but you might like to start with these discussions:
"When and how did the concept of lock and key develop?" : by /u/schuylertowne . "before then" is the lower reply if sorted in "top" order, "first become" is the top reply (just cudderisback copy and pasting an earlier reply by schuylertowne).
If you're curious about Rome in particular, even though it's after that time, /u/mythoplokos has a reply at "Did people in antiquity have keys for their homes?" .
This is not to discourage discussion. Further questions, data, and debate are always welcome.