Reiko asked an interesting question today, and it made me want to run out and research it right away. Unfortunately we weren't anywhere near a library so I had to wait until we got home to do the digging. The question was a rather simple one, and I'm surprised it hasn't come up more often from the people around me over the years: why is Japan called Japan in English when the proper name is 日本 (usually pronounced 'Nihon' and 'Nippon' for official purposes)?
Wikipedia has a really good explanation going through the history of Japan's names from before the 8th Century up until now, and it's a great read even if you don't know much about the country's past. The gist of the story is this: before Western nations directly contacted the secluded people living on the islands of 日本, they spoke to the Chinese. Translations from Chinese to Portuguese were incomplete, but that information was later disseminated among the elite in Europe where the Romanized name of Japan eventually took root. Eventually that name was brought to 日本 and adopted for use with international branding.
And now we know.