Wasn't Thanksgiving a practice before people came to the US? The US now does it, but they didn't start it. I only know it because I'm Dutch and I wanted to see if the Dutchies were somehow involved (because they are way more often than they should be). Here's a source I quickly found but there are many sources on it [1].

There's more to Thanksgiving than only the US.

[1] https://www.iamexpat.nl/lifestyle/lifestyle-news/how-netherl...