There has been a growing movement to change the name of Columbus Day, which has been a federal holiday since 1934. Some activists say that celebrating it ignores the atrocities committed by Christopher Columbus and other European explorers against the indigenous people they encountered. A troubling testament to the terrible actions committed by Columbus and his men came from a study earlier this year, which found that so many Native Americans died from a combination of massacres and disease in the 16th and 17th centuries — around 56 million— that the earth’s climate actually cooled 0.15 degrees Celsius as agricultural land was abandoned back to forests and other plants. Oregon, Minnesota, South Dakota, Alaska, North Carolina, and New Mexico have all renamed the holiday that falls on the second Monday of October, as have at least 130 cities and towns. This week, Maine joined that list to become the seventh state in the US to replace Columbus Day with Indigenous Peoples’ Day in honor of America’s first inhabitants.