New Jersey continued to grow after the Civil War, and the industrial revolution was under way. Many factories opened, and cities like Camden, Paterson, Newark and Trenton got bigger as immigrants came from Europe to work in the factories. In order to transport materials, railroads were laid to connect the cities. In the beginning, immigrants came from Ireland and Germany. Later on people would come from Italy and countries throughout Eastern Europe. Half the state’s population was born or had parents who were born outside the United States in 1910. Farm populations shrank as the cities population’s grew. With many people working in the factories, child labor and protection for workers became important. The state’s economic expansion had a lot to do with the genius of it’s inventors. Thomas Edison is the most famous. The light bulb, along with thousands of inventions helped develop a motion picture while working in New Jersey. In the early 1900's, Fort Lee, New Jersey became the motion picture capital of the world.