What do you mean "first country ever"? Racism, slavery, etc. has been around since the Book of Genesis in The Bible.
And we're not the only country - at least we don't try to do genocide: not openly anyways. I believe more countries are racist than are not racist.
You can't just look back 100 years or so. As long as humans have greed, hate, lust, etc. there will be racism, prejudice, and all those other ideas where people think they are better than someone else based on color of skin, nationality, gender, sexual preferences, etc.
And how can we be so racist if we recently elected a black president?
A country of Equality? No way at all. Are many Americans racist? Absolutely! But we are surely not in any exclusive club by that benchmark.
It's humans in general that are racist and not any one country in particular.