Question

In the late 1800s, the building of railroads in Europe led to an increase in U.S.

Answer 1

As Europe grew more and more connected, western Europeans believed that the way to create a better future for them and their families was to leave Europe and come to America where they'd have better opportunities and the idea of a new world that was being founded by whoever came. That led to a lot of western Europeans, British, Spanish, Irish, migrating from Europe to America in the late 1800's.

Hope I can help you!