<Tr> <Th> First release </Th> <Td> Rainbow Six August 21, 1998 </Td> </Tr> <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>

Where does the name rainbow six come from