Ganna (seeress)

Further information: Seeress (Germanic)
It appears to have been Ganna herself, and her king Masyus, who informed Tacitus of the Semnoni religious practices. An illustration of the Semnoni sacred grove, which is identified with the Grove of Fetters in Scandinavian heroic legend.

Ganna (Greek: Γάννα) was a Germanic seeress (also called priestess), of the Semnoni tribe, who succeeded the seeress Veleda as the leader of a Germanic alliance in rebellion against the Roman Empire. She went together with her king Masyus as envoys to Rome to discuss with Roman emperor Domitian himself, and was received with honours, after which she returned home. She is only mentioned by name in the works of Cassius Dio, but she also appears to have provided posterity with select information about the religious practices and the mythology of the early Germanic tribes, through the contemporary Roman historian Tacitus who wrote them down in Germania. Her name may be a reference to her priestly insignia, the wand, or to her spiritual abilities, and she probably taught her craft to Waluburg who would serve as a seeress in Roman Egypt at the First Cataract of the Nile.

Ganna and the other Germanic seeresses served an important political role in Germanic society, and the Romans always had to take their opinions into account when interacting with the Germanic peoples east of the Rhine.