This Rebel Alliance symbol from Star Wars will doubtless be recognizable to many. A Celtic version was a unique request from someone who joyously embraces his inner Geek, and now has fully externalized it. Since I stopped watching TV before it appeared, I'd never heard if it; so it was something I had to Google up in Image Search. Just now when I tried to get more information so I could describe just WHO the Rebel Alliance were I found pages of links to fanboy obsessions, more than I could sift through. So I'll leave it that I fulfilled a strange assignment to the satisfaction of the client.
Star Wars 'Rebel Alliance' Celtic Knot Tattoo by Pat Fish