<Tr> <Th> Latest release </Th> <Td> Rainbow Six Siege December 1, 2015 </Td> </Tr> <P> Tom Clancy's Rainbow Six is a media franchise created by American author Tom Clancy about a fictional international counter-terrorist unit called "Rainbow". The franchise began with Clancy's novel Rainbow Six, which was adapted into a series of tactical first - person shooter video games . </P> <P> Rainbow Six describes Rainbow as an international counter-terrorism operation hosted by NATO and funded by money funneled through the U.S. Department of the Interior . </P> <P> The base of operations for Rainbow is located in Hereford, England (at the time, home to the SAS), due to the United Kingdom being one of the most accessible countries in the world and having one of the world's foremost special forces units . Most of the characters in Rainbow Six are American or British, though the NATO countries of France, Germany, Italy, Spain, Canada, and the NATO ally of Israel have at least one representative each . </P>

Where did the name rainbow six come from
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