Europa Casino is regulated by kahnawake and powered by Playtech casino games. Both kahnawake and Playtech do not accept citizens from the United States of America.
I sent an email to the Europa Casino support to get a clear explanation. Here is their answer :
This is Anjo from the Europa Casino Support Team.
Please be informed that we are not currently accepting players from US.
You may check our website's Terms and Conditions for further information:
As part of the US gambling law, Europa Casino preferred to step back from the US Markets. However, some online casinos still continue to accept US citizens. Check our top 3 US Casinos.
Technically, you could play to Europa Casino if you signed up from abroad. For instance if you are in vacation in Indonesia or in South Africa, you could play to Europa Casino while you drink your Caipirihna. However, you should not use a US address and an american credit card (from Wells Fargo for instance).
This is the same problem as "signing-up from abroad". You could use a VPN to play to Europa Casino, but you would need to have a real address outside of the US (with rent receipt at your name for instance). If you have a cousin abroad, for instance in the Australia, it could work. Otherwise, in case you win a $3,000,000 jackpot, Europa Casino could block your funds..
We know that Bovada is currently accepting US citizens. It is powered by Top Game software and offers a nice welcome bonus.