Question

What was the name of the island on the East Coast, where thousands of immigrants were processed before coming into the country?

Answer 1

Ellis Island was the hub for millions of immigrants coming into the United States. Ellis Island functioned as the the first stop for immigrants coming into the United States from 1892 until 1954. Ellis Island now serves as a museum of the long immigrant history of the United States. 

Answer 2

Eastern Europeans were processed through Ellis Island, near the Statue of Liberty. About 98% of ALL immigrants made it through Ellis Island with no problems. The same could not be said for the Asians who came through the West Coast facility--Angel Island. 
Nearly ALL Asian immigrants came to America through the west coast processing center located on Angel Island, right by Alcatraz Island off the coast of San Francisco. Only about 65% of all Asians made it through the rigorous process on the west coast and many were delayed there for days, weeks or even months while the processing droaned on and on.