Apparently Japan was first electrified by the British, who use 50Hz.
Then the US bombed the country (something about a little picadillo called WW2).
When the US rebuilt the destroyed parts of the electric system after the war they used the 60Hz US standard frequency.
Thus arose the unique situation that if your job transfers you from one end of the country to the other you may not be able to take all of your appliances with you to your new home.
