Kumbi, also called Koumbi Saleh, last of the capitals of ancient Ghana, a great trading empire that flourished in western Africa from the 9th through the 13th century. Situated about 200 miles (322 km) north of modern Bamako, Mali, Kumbi at the height of its prosperity, before 1240, was the greatest city of western Africa with a population of more than 15,000. Within its boundaries there were—as was the custom of the early kingdoms of the western Sudan—two cities, one of which was occupied by the king, the other by Muslim traders.
Ireland. The Irish potato famine brought Irish (and German at the time seeking religious and political freedom) which immigrated to America, threatening the jobs Americans had due to their low wage.