There hasn't been a country who said that bitcoin is totally "illegal" those who made some regulations are China, Usa and probably the India, but they didnt said that bitcoin is ilegal, a regulation is something completely different. Just remember that China is not killing anyone just because using bitcoins, they are only shutting down some exchanges in their countries, but nothing more.
Bitcoin is legal in most countries all around the world.
Your information about bitcoin is NOT illegal in any country needs correction (no offense). There are at least four countries which have banned bitcoin completely. Namely Bolivia, Ecuador, Bangladesh, Kyrgyzstan.
* Here Bolivia banning bitcoin in 2014.
* Ecuador went one step further and banned the bitcoin and all other digital crypto currencies which are decentralized by the National Assembly of Ecuador
* National Bank of the Kyrgyz Republic specifically mentioned the bitcoin while imposing ban on the virtual currency in its law.
* The law in the Bangladesh are very strict than above all combined as Bangladesh Bank said that "anybody caught using the virtual currency could be jailed under the country's strict anti-money laundering laws" .
From above we could see that out 195 countries in the world only four have banned the bitcoin. In countries where bitcoins is not declared illegal is deemed as legal. Understanding of law is such that if something is not illegal it is considered as legal. Because we can not mention or list everything under the Sun that is legal, but we could mention what is illegal.