[gamechangr]

It seems like you missed one critical category.....

"Second language" language use by population

I personally considered the same question, except that I wanted to know second language by location.

I am from the US and speak four languages. I wanted to know if I traveled, where in the globe would be most difficult with English/Spanish as a first or second language.

[benrudolph]

Totally agree with you. Second language statistics are a bit harder to track down. It's something I'll look into. English as a second language is probably your biggest help. I'm not sure of any countries that consistently teach Spanish as a second language outside of the Americas.

[gamechangr]

Good point! I looked for English, Spanish, Farsi, and Russian. For me, the obvious choice of Mandarin was left.

Your article mentioned German and French.

What do you think the second language of Europe would be?