Railroads built in mexico touched the lines of United states which made many immigrants to visit America as a trip.
Explanation:
There were many barren lands which were in south-western United States and they were converted to a fertile farmland under the Newlands Reclamation act. Cotton plantations were set up and it required much workers to work in cotton plantations. This employment opportunity largely attracted the Mexicans to migrate to america. They became the dominant labor force in the south west of America.
In 1920s , industrialization occurred in America which made factories to be set up. This also attracted huge Mexican population to migrate to America for better living and economic conditions. They crossed the border as the American industries needed them.
