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
United States of America Mathematical Olympiad United States of America Mathematical Olympiad The United States of America Mathematical Olympiad (USAMO) is a highly selective high school mathematics competition held annually in the United States. Since its debut in 1972, it has served as the final round of the AMC series of contests. The United States of America Junior Mathematical Olympiad (USAJMO) was introduced in 2010 to recognize top scorers based on their AMC10-based index. Qualifying for the USAMO is considered one of the most prestigious awards for high school students in the United States. Top scorers on the USAMO are invited to the Mathematical Olympiad Summer