The countries in which Bitcoin is considered legal are those in which regulations are slightly more advanced than in others. However, most countries fall in between legality, because although the use of the cryptocurrency is not outright forbidden, there are also no real guidelines present.
If im not mistaken there are very FEW countries where bitcoin is ILLEGAL. It is however not regulated in a large portion of countries.
Russia is really advancing with crypto when it comes to regulations, excited to see what their plans are.