- Cabrakaän (Symphonic / Folk-metal)
- ‡ Cadacross (Melodic/Death/Folk/Metal)
- ‡ Caladmor (Epic Folk-metal)
- Calico Jack (Pirate Folk-metal)
- Cân Bardd (Folk/Black Metal)
- Cantus Levitas (Mittelalter Rock/metal)
- Captain Jack’s Army (Speedfolk)
- ‡ Cat O’ Nine Tail (Pirate metal)
- ‡ Catuvolcus (Folk/Black Metal)
- ‡ Cave Growl (Alcoholic Folk-metal)
- ‡ Caverns of Arnosh (Folk-metal)
- Celestic (Heroic Melodic Death Metal)
- Celkilt (Folk-punk)
- Cellar Darling (Folk-metal)
- Celtachor (Celtic/Folk/Black Metal)
- Celtian (Symphonic Folk-metal)
- Celtibeerian (Folk-metal)
- ‡ Celtibeers (Folk-metal)
- Celtica (Celtic Pipe Rock)
- Celtic Legacy (Folk-metal)
- Cemican (Prehispanic Folk-metal)
- Ceolskog (Acoustic/Folk-metal)
- ‡ Cerberus (Atmospheric/Folk Metal)
- Cernunnos (Folk-metal)
- Cernunnos’ Folk Band (Folk-metal)
- Chain of Dogs (Folk/Thrash/Punk)
- The Chant of Trees (Mediative Folk-metal)
- Ch’aska (Folk-metal)
- Chur (Folk-metal)
- ‡ Circle J (Folk-punk)
- ‡ Circle of Grief (Gothic Metal/Folk)
- ‡ Circle of Tyrants (Folk/Black Metal)
- Claim the Throne (Melodic/Death/Folk-metal)
- ‡ Clamor Silvae (Folk Viking-metal)
- The Clan (Irish Rock)
- ‡ Clanrock (Folk-metal/Celtic Rock)
- ‡ Cnoc An Tursa (Folk/Black Metal)
- Codex Verus (Medieval Rock)
- ‡ Conorach (Folk/Power Metal)
- Corte di Lunas (Renaissance Celtic Folk Rock)
- Corvidae (Medieval Rock/Metal)
- Crash Nomada (Folk Punk)
- The Crazy Rogues (Celtic Punk)
- Crescent Lament (Folk-metal)
- ‡ Crimfall (Symph. Power/Folk Metal)
- Cronica (Folk-metal)
- Cruachan (Celtic/Folk Metal)
- Cruadalach (Folk-metal)
- ‡ Cryptic Age (Progressive Folk-metal)
- Crystalmoors (Cantabrian Pagan Metal)
- ‡ Cultus Ferox (Medieval Rock)
- ‡ Cumulo Nimbus (Renaissance Metal)
- Curare (Andean Folk-metal)