English
English is the # 1 language on the Internet
http://www.internetworldstats.com/stats7.htm
English is spoken in 110 countries
https://www.scmp.com/sites/default/files/2015/11/25/languageshqscmp.png
Places where English is a key language
http://en.wikipedia.org/wiki/Image:Anglospeak.svg
Biggest movements of people during the last 5000 years
http://www.youtube.com/watch?v=QOSPNVunyFQ
English is part of the Germanic languages
http://upload.wikimedia.org/wikipedia/commons/4/4f/IndoEuropeanTree.svg
An English-speaking learner of German will notice how many English words seem to come from German. Examples Water / Wasser. Bread / Brot. House / Haus. http://www.economist.com/blogs/johnson/2012/12/language-families
From about the 700th, Danish Vikings merged into the English population. Old Norse mixed with old English. Sources http://youtu.be/kIzFz9T5rhI Diamond, Jared: Collapse, p. 184. https://youtu.be/YEaSxhcns7Y