The first great civilization in Mexico was the Olmecs

Between 1400-300 B.C., the Olmecs established many cities along the eastern coast of Mexico, sculpted the famous Colossal Heads, and worshipped a mysterious, unnamed god that was part human and part jaguar.
The official name of Mexico is Estados Únidos Mexicanos
Don't be surprised if you get funny looks when you tell people in Mexico . . .