Others have stated Ecosia/Qwant building a European search index, but you also have Mwmbl with their own index that I believe is not American.
Additionally, you could also look at the various SearXNG instances hosted in Europe (or self-host your own!). They are meta search engines, meaning you can configure what sources and indexes they use for results and the ones you select are used together.
What is a fully US independent search engine?
Others have stated Ecosia/Qwant building a European search index, but you also have Mwmbl with their own index that I believe is not American.
Additionally, you could also look at the various SearXNG instances hosted in Europe (or self-host your own!). They are meta search engines, meaning you can configure what sources and indexes they use for results and the ones you select are used together.
Qwant
Not entirely, as currently, beside results from their own index, they also add search results from Bing.
Qwant and Ecosiaia are currently building a joint independent index
Yes, I know, that’s why I wrote “also”. I’ve edited my comment to make the point more clear.