Issues of health and healing have helped to shape the African-American experience since the first Africans came to America. Inhuman conditions on slave ships, and later inadequate, crowded, and unsanitary living conditions caused slaves great concern. Enslaved Africans in the United States brought with them from their homeland knowledge of herbs, barks, and other items found in everyday life and successfully developed many useful medicines that black and white practitioners used early on. They knew that a wide variety of mineral, plant, and herbal concoctions had medicinal value. Although plantation rules were stringent, slaves chose self-treatment or medicine dispensed by herb or root healers. They believed that many of their illnesses were caused by demons and therefore sought such curative measures as charms, incantations, and rituals that required medicine men and “conjure women” to drive away evil spirits. To them, demons were the cause of many illnesses prevalent during that period.