During the last fight, we can see many explosions. Although gun power has already been invented in China, but the European would have to wait several centuries to have the technology.
Azeem (sic?) is a Muslim from the Middle East, which is part of the continent of Asia. I know its not exactly close to China, but the ancient Chinese empires of this time traded consistently with the Arabs of the Middle East. So you have to concede that it is at least possible that he had learned of the existence of gunpowder through trade with China, or perhaps he even traveled to China himself. I realize this is all a bit of a stretch, but it is possible--unless gunpowder had not yet been invented; which I am not sure about.
Yes we actually know that Azeem does have gunpowder!! Do you remember he was demonstrating it in the fire, while the party was going on? They ask how he does that, and he exclaims that it's all in the black powder!
The time of Robin Hood (actually Robin of Locksley) is between 1188 and 1199...In 1188, Richard Coeur de Lion (the Lion-Hearted) was crowned King of England after the death of his older brother and his father. The year 1194 is when Richard returned to England to get rid of his wayward brother. He went off to fight the Third Crusade in 1190 and in that time is when the story of Robin Hood takes place; when his younger brother, Jean-Sans-Terre (Prince John or John without land) ran the country in his absence.
The Chinese invented gunpowder around 1040. The Chinese did trade very heavily with the Arabs. It might have been possible that they received gunpowder in a trade, but the Arabs first use of gunpowder as a weapon didn't come until the 14th century. So no, gunpowder was not invented 1000 years before, and although it's plausible that Ahzeem's Middle Eastern (although I thought he was a Moor which is North African, not the Middle Eastern) background could have introduced him to gunpowder it would have been long after the time of this story. Whodathunk all that French history would come in handy one day...on a website, about a movie.
Gunpowder had been invented, in China, at the time the film is set. It is possible that Azeem learned of it while in the middle east. Judging by his telescope, Azeem seems to have a penchant for the latest gadgets of the day!!