Netbird is a European company headquartered in Berlin. It's fully FOSS and you can self-host the entire stack, unlike Tailscale which relies on a third party implementation.

There's a script on their github that makes setup super easy.

That said, I've no idea where their servers are, if you opt to use their servers instead of hosting your own.

Edit: oh yeah, they also have a YouTube channel with updates and guides.