Those collections had been built over generations.

Some remains came from archaeological excavations.

Others were collected by government expeditions, universities, private collectors, or institutions that treated Native burial places as sources of scientific material.

The law forced a reckoning.

Museums had to inventory collections and consult tribes.

Human remains that had long been stored in boxes, cabinets, and laboratory spaces became the subject of legal and ethical review.

Progress was uneven.

Some institutions built strong consultation relationships and returned ancestors.

Others moved slowly, disputed affiliation, or relied on narrow evidentiary standards that made repatriation difficult.

Very ancient remains were among the hardest cases because institutions often argued that the passage of time made cultural affiliation impossible to establish.