 This period of growth also resulted from the waves of European immigrants, mainly from Croatia and Russia attracted to the gold rush and sheep farming boom in the 1880s and early 1900s.The largest sheep company, controlling 10,000 square kilometres in Chile and Argentina, was based in Punta Arenas, and its owners lived there.Since its founding Chile has used Punta Arenas as a base to defend its sovereignty claims in the southernmost part of South America.