Complex sentence: In 1875, Congress passed the Page Act, the first restrictive immigration law, which identified forced laborers from Asia and Asian women who would potentially engage in prostitution as "undesirable" are barred their entry into the United States.
Split into simpler sentences: In 1875, Congress passed the Page Act, the first restrictive immigration law. This law identified forced laborers from Asia as well as Asian women who would potentially engage in prostitution as "undesirable" persons, who would henceforth be barred from entering the United States.