I know that Japan and Korea are two countries that recently accepted bitcoin. In Japan, the exchange market occupies more than 50% of the market share of many Bitcoins in Japan. Volume of Bitcoins increased from 1,845 to 97,815 in 2016, an increase of 53 times. Because people like to use bitcoins to pay and reserve, so Bitcoin in this country is quite high.
I think there is a lot of confusion and use of the wrong terminology
particularly the word "Legal". Japan has not legalised Bitcoin they
announced in the last few weeks that they are recognising Bitcoin
as a form of payment which is slightly different.
I guess recognizing some currency is almost similar to making it legal. If government is allowing public to deal in bitcoins, that means they are making it legal. Japan is one of the countries having highest number of bitcoin holders, so there government is sooner forced to make it legal if they have not yet. Just like India has recently made bitcoins legal.