Mission San Luis Rey de Francia was the 18th of the California Missions founded on June 13, 1798. Known as the 'King of the Missions', it was once one of the largest at 950,000 acres in its prime and had a population of almost 3,000. The mission was named after King Louis IX of France for his Holy Land crusades of the 13th century. Life was difficult for the Luiseño Native Americans who lived here because of the new lifestyle and diseases brought over. By the time the Mission system had ended, their population dwindled by almost forty percent.