Question

what group of immigrants arrived in large numbers on the US West Coast for primary purpose of working on the Transcontinental Railroad in the 19th century

Answer 1

I would have to say either Chinese immigrants or Irish immigrants. There were large groups of these ethnicities working on the Transcontinental Railroad.

Answer 2

Answer: Chinese immigrants

Chinese immigrants who arrived during the 19th century were mainly employed in the construction of the Central Pacific Railroad. Some also joined other industries, such as mining. They were often victims of racism and segregation at every level of society. This opposition to Chinese immigration culminated with the passage of the Chinese Exclusion Act of 1882, which prohibited immigration from China for ten years.