Question: How many immigrants crossed through the gateway predecessor of the first American immigration station?

Context paragraphs:
Immigration from China in the early 20th century: Immigration from China in the early 20th century is an article on Chinese immigrants to the United States in the early twentieth century, even with the Chinese Exclusion Act in force was passed in 1882.  4441 of them came to the USA through the Ellis Island Immigration Station, while others came to the USA through other immigration stations throughout the country such as the Angel Island Immigration Station in California.  In all, 66,946 immigrants from China came to the USA from the beginning of the twentieth century to 1931.

American Immigration Council: The American Immigration Council is a Washington, D.C.-based 501(c)(3) nonprofit organization and advocacy group.  It studies immigration to the United States, advocates for undocumented immigrants in the United States, and attempts to educate the public on what it describes as "the important and enduring contributions that immigrants make to America."  It was established in 1987, originally as the American Immigration Law Foundation, by the American Immigration Lawyers Association.

Angel Island Immigration Station: Angel Island Immigration Station was an immigration station located in San Francisco Bay which operated from January 21, 1910 to November 5, 1940, where immigrants entering the United States were detained and interrogated.  Angel Island (California) is an island in San Francisco Bay.  It is currently a State Park administered by California State Parks and a California Historical Landmark.  The island was originally a fishing and hunting site for Coastal Miwok Indians, then it was a haven for Spanish explorer Juan Manuel de Ayala.  Later, it was developed as a cattle ranch, then, starting with the Civil War, the island served as a U.S. Army post.

Pier 21: Pier 21 was an ocean liner terminal and immigration shed from 1928 to 1971 in Halifax, Nova Scotia, Canada.  Over one million immigrants came to Canada through Pier 21 and it is the last surviving seaport immigration facility in Canada.  The facility is often compared to the landmark American immigration gateway Ellis Island.  The former immigration facility is now occupied by the Canadian Museum of Immigration, the Nova Scotia College of Art and Design as well as various retail and studio tenants.

Bernard Wolfsdorf: Bernard P. Wolfsdorf is an American immigration lawyer, the past President of the American Immigration Lawyers Association (AILA).  He is the founder and Managing Partner of Wolfsdorf Immigration Law Group, located in Los Angeles and New York.

Emergency Quota Act: The Emergency Quota Act, also known as the Emergency Immigration Act of 1921, the Immigration Restriction Act of 1921, the Per Centum Law, and the Johnson Quota Act (ch.  8, 42 Stat.  5 of May 19, 1921) restricted immigration into the United States.  Although intended as temporary legislation, the Act "proved in the long run the most important turning-point in American immigration policy" because it added two new features to American immigration law: numerical limits on immigration and the use of a system for establishing those limits.  These limits came to be known as the National Origins Formula.

Ellis Island: Ellis Island, in Upper New York Bay, was the gateway for over 12 million immigrants to the United States as the nation's busiest immigrant inspection station for over sixty years from 1892 until 1954.  The island was greatly expanded with land reclamation between 1892 and 1934.  Before that, the much smaller original island was the site of Fort Gibson and later a naval magazine.  The island was made part of the Statue of Liberty National Monument in 1965, and has hosted a museum of immigration since 1990.

Castle Clinton: Castle Clinton or Fort Clinton, previously known as Castle Garden, is a circular sandstone fort now located in Battery Park, in Manhattan, New York City.  It is perhaps best remembered as America's first immigration station (predating Ellis Island), where more than 8 million people arrived in the U.S. from 1855 to 1890.  Over its active life, it has also functioned as a beer garden, exhibition hall, theater, and public aquarium, and currently is a national monument.

Charles Foster (attorney): Charles C. Foster is an American immigration attorney and chairman of the Houston-based law firm Foster LLP.  Foster has earned top awards from organizations including Chambers and Partners, Texas Monthly magazine, and the American Immigration Law Foundation.  He also serves as the Honorary Consul General of the Kingdom of Thailand in Houston and has received four Royal decorations from His Majesty, King Bhumibol Adulyadej of Thailand.

Michael Wildes: Michael Jay Wildes (born November 27, 1964) is an American immigration lawyer and politician who served as the 36th Mayor of Englewood, New Jersey.  A member of the Democratic Party, Wildes served as a Federal Prosecutor for the Eastern District of New York and as a City Councilman for Englewood before he was elected mayor in 2003.  He was reelected in 2006.  A nationally recognized authority on American immigration law, Wildes has been called "attorney to the stars" for his success in defending the immigration rights of his clients, many of whom are celebrities.  Wildes is the managing partner of the law firm Wildes and Weinberg PC.  He also serves as immigration counsel to Pavia & Harcourt LLP, Saiber, and Lincoln Center for the Performing Arts.

Supporting paragraphs: Castle Clinton Ellis Island
Answer: 12 million