History of immigration to the United States 1850. In 1848, the Treaty of Guadalupe Hidalgo, concluding the Mexican War, extended U.S. citizenship to approximately 60,000 Mexican residents of the New Mexico Territory and 10,000 living in California. An additional approximate 2,500 foreign born California residents also become U.S. citizens. In 1849, the California Gold Rush attracted 100,000 would-be miners from the Eastern U.S., Latin America, China, Australia, and Europe. California became a state in 1850 with a population of about 90,000. Between 1850 and 1930, about 5 million Germans migrated to the United States, peaking between 1881 and 1885 when a million Germans settled primarily in the
Presbyterian Church in the United States of America of the Dutch Reformed Church (now the Reformed Church in America) and the Associate Reformed Church, to form the United Foreign Missionary Society. The United Society was particularly focused on work among Native Americans and inhabitants of Central and South America. These denominations also established a United Domestic Missionary Society to station missionaries within the United States. In 1826, the Congregationalists joined these united efforts. The Congregational mission societies were merged with the United Domestic Missionary Society to become the American Home Missionary Society. The Congregational American Board of Commissioners for Foreign Missions (ABCFM) became the recognized missions agency of