There is an interesting example of a mixture of the medieval and the modern in Tolkien's portrayal of the Gondorian Rangers of Ithilien. They were dressed in a mixture of green and brown for camouflage purposes, and operated from secret bases in Ithilien, which Gondor still claimed as part of its territory, against Sauron's forces. Among their weapons, they used longbows.
It made me think of the legend of Robin Hood and his Merry Men, dressed in Lincoln Green, living in Sherwood Forest, and using longbows. However, I also thought of more modern things; because the Gondorian bows were made of steel, not yew, the green and brown sounding like more 'modern' camouflage uniforms. Also, the Rangers sounded like the Auxiliary Units, planned by the United Kingdom in the Second World War in the event of a German invasion, intended to fight as uniformed guerrillas. They were organised as part of the Home Guard, and wore Home Guard uniforms, but practiced guerrilla warfare and would fight under state appointed commanders.
What do people think?
