The four decades between 1873 and 1913 revolutionized the world. Population and its migration increased by significantly higher rates than ever before, so that its distribution around the world also changed noticeably. Previously sparsely settled regions in North and South America, Oceania, and Siberia were settled by tens of millions of Europeans. Already previously settled areas of South, Southeast, and Northeast Asia attracted also tens of millions of Indian and Chinese migrants, many of whom later returned home. Rural-urban migration and urbanization increased markedly, both to and in existing cities within countries and to new ones in the regions of recent settlement.