This is a tricky question to answer. On the one hand, we could say Bitcoin is non-jurisdictional. If Bitcoin is out of a government’s jurisdiction to officiate, then it can’t be illegal to use it. That’s true, but that only relates to half of the question. The legality of gambling – with any form of currency, or “thing of value”, as every local laws define it – is decided on a jurisdictional basis.
If you scour the internet for an answer to this question, you’ll find that most people say Bitcoin gambling is legal, not just here, but there, and everywhere. Those people are referring to the Bitcoin aspect more so than the gambling / online gambling aspect of the query.
That would be like saying, “It’s illegal to buy an AK-47, unless you buy it with Bitcoin. Then it’s okay,” or, “It’s illegal to bribe a police officer, unless you bribe him with Bitcoin.” No, sorry, fully automatic rifles and police bribery are illegal, no matter how you attempt to pay for it.
What we have to do is answer these two questions separately, dealing first with the global legality of Bitcoin, then with the jurisdictional legality of online gambling.