Everyone thought these helmets were Roman until scientists uncovered the truth
Researchers have solved a decades-old mystery by showing that a cache of 43 helmets found off the Spanish coast is medieval, not Roman. The remarkable discovery exposes a thriving weapons trade network that connected Mediterranean powers during a time of piracy, warfare, and growing demand for…
Attribution as a function of expectations—for decades, everyone "saw" Roman helmets because they expected to find them. A classic example of theory-dependent observation.