When populating my fictional music festival with bands, I used some I had prepared earlier, for other books. I needed some new ones, and one I came up with I called Fusilier. This is composed of men and women who wear period military uniform and play kettle drums and fifes. When I invent this kind of thing, it generally just comes to me, but I sometimes deconstruct the process afterwards.
In the case of Fusilier, I believe one of the sources was probably a Eurovision act I saw a few years ago. The song was called Only Teardrops and the introduction consisted of drummers and flutes. The fifes may have come from the Punchbowl Farm series of books which I read in the 1960s and 70s. In one of the stories Lindsey, who had been saving up for a flute, bought a fife instead because it was less expensive. I remember knowing what a fife was because of the old song Soldier Soldier. Finally, there's the poem Following the Drum and, even longer ago, a book called The Ship from Simnel Street. So, there you are... the band Fusilier... It just came to me. Or did it?