The US Department of the Interior (DOI) reported Wednesday that 53 marked or unmarked burial sites were discovered at federal boarding schools for Native Americans. The investigation is part of the ongoing Federal Indian Boarding School initiative, a government effort to address the dark history of federal boarding schools for Native Americans. From 1819 to 1969, the US operated boarding schools for Native Americans in 37 states. The schools functioned under a joint objective of cultural assimilation and territorial dispossession of indigenous peoples through forced relocation. According to the report, schools were only listed as Native American boarding schools if they provided on-site housing or overnight accommodations, provided formal academic or vocational training, received federal funding or support, and operated before 1969. According to those ratings, the report uncovered 408 schools, including 21 in Alaska and 7 in Hawaii. More than 1,000 additional federal and non-federal institutions were also discovered, including Native American day schools, asylums, orphanages, and independent dormitories. Wednesday’s report marks the first time the US government has inventoried and mapped the location of these schools and released the results. According to the report, the schools employed systematic militarized and identity-altering methodologies. Native American boys were subjected to name changes and haircuts, prevented from using their native language or cultural practices, and ordered to perform military drills and manual labor. Native American children who resisted these methodologies suffered punishment, including corporal punishment. The report also detailed the discovery of Native American boarding school burial sites, which were discovered in approximately 53 different schools. The researchers found a total of 33 marked, 6 unmarked, and 14 marked and unmarked burial sites. The DOI decided not to disclose the locations of the burial sites, citing concerns of grave robbing and vandalism. Initial analysis indicates that 19 Native American boarding schools accounted for more than 500 child deaths. DOI expects the number of child burial sites and deaths to increase. The investigation is expected to continue with funding from Congress for at least the next year. Secretary Deb Haaland said she hopes the investigation will give a “voice to the survivors and descendants of federal Indian boarding school policies” and address “the lasting legacies of these policies so that Indian peoples can continue to grow and heal.” Haaland is the first Native American to serve as a cabinet secretary.