The thunderbird is a mythological bird-like spirit in North American indigenous peoples' history and culture. It is considered a supernatural being of power and strength.[1]

The thunderbird is said to create thunder by flapping its wings (Algonquian[2]), and lightning by flashing its eyes (Algonquian, Iroquois[3]). Across cultures, thunderbirds are generally depicted as birds of prey, or hybrids of humans and birds.[1] Thunderbirds are often viewed as protectors, sometimes intervening on people's behalf, but expecting veneration, prayers, and gifts.[1]

Archaeologically, sites containing depictions of thunderbirds have been found dating to the past 4000 years.[1]

Petroglyphs of thunderbirds are found near Twin Bluffs, Wisconsin. They are in a shelter that was probably used c. 250 BCE to 1500.[4] - Source Wikipedia https://en.wikipedia.org/wiki/Thunderbird_(mythology)