Africa, Latin America excluding Argentina, South East Asia, most of the Middle East and Central Asia and on most dimensions India.

The US is still a fairly homogenous place. Only 20% of the population is bilingual compared to over 60% of the world, only 7% follows non-Christian religions.

Brazil, Nigeria, Indonesia, Singapore, the 'stans', Lebanon, the UAE of the top of my head places where within probably an hour of arriving you'd notice you are in a much, much more diverse place.