What does 'Manifest Destiny' refer to?

Hi Gino! Great question. Manifest destiny was a belief that was was prevalent in the 19th-century United States. It stated that American settlers had the right and duty to expand across North America (this expansion is the destiny that was being manifested, so to speak). That belief led to a lot of violence by settlers (primarily of European descent) against indigenous peoples of the continent and has ramifications that persist until today.