Are you American if you were born in America but speak Russian?

Nationality is subjective, since some people consider where they were born to be their nationality while others consider where they currently live to be their nationality.

Language tends to not influence nationality. For example, if you were born in Russia but moved to America and speak english, you could still very well say you're Russian since it's where you were born.

Language doesn't generally determine nationality, but people can identify with any nationality they choose.