The zpool history <poolname>
command will show you dataset creations and destructions, snapshot creations and destructions, snapshot sends and receives, clone creations and promotions, key changes, keys loaded and unloaded, and a bunch of stuff, really. It's like a built-in "ledger" for your pool that is independent of the operating system.
You can use "grep" to filter the results.
How large can the zpool history log be? I never quite figured it out. Apparently it's a tenth of a percent of your pool's size, but this is old information.