At the beginning of the seventh century, the migration trend began to flow from Europe to North America. For more than three centuries, only hundreds of English people migrated on a large scale at first, and millions of people gradually became the potential force of the flood-like migration. Driven by various powerful motives, they finally established a new civilization on this once barren continent. John, the second president of the United States, the American revolution began at 1620. The open division between Britain and the United States was the beginning of the 1763 and 18 12 wars. It can be said that the United States has reached a mature age in the second independent war of the two wars-the Civil War and the First World War. In less than fifty years, it has changed from a rural-based republic to an urbanized country. 19 14 The war broke out in Europe, which shocked the American public. On April 25th, the European War was drawing to a close, and representatives from fifty countries met in San Francisco to draft the organizational structure of the United Nations. Translate in English, don't translate by yourself with an online translator.