In the US, tie-dye is deeply connected to hippies and the 1960s; however, the method of selectively dyeing cloth by twisting and tying it is both older and more widely- spread than that (source).
Shibori is the Japanese art of dying cloth this way, and has been practiced in that country since at least the 700s CE (according to a Wikipedia page with no source given…). There are significantly more methods than you learned at summer camp; Arashi Shibori, which is wrapped around a pole, and Nui Shibori, which involves stitching, are just two examples. More can be found here.
The basic technological requirements for this technique are the ability to make cloth, to dye things, to tie knots, and for certain techniques, to do complicated needlepoint. Most of these technologies flow into each other; people who can weave usually can tie and sew, and vice-versa. Who performs the techniques depends on how expensive or cheap dye and cloth is, and whether spending time on appearance is considered fitting for that group. But at it’s heart, Shibori is a potentially universal art.
What all of this really means, though, is that you can totally incorporate tie-dye hippie clothes from the thrift store into your costume! Or, if you’re a game designer, into your universe. In either case, have fun!
Tie Dye Cotton Thai Fisherman Capri Leg in Dark Violet via Shades of Siam. Cotton. Ships worldwide. £13.46 GPB