There was a group of young european workers that came to America from early 17th to early 20th century. These inmigrants would get a contract to work for an american employer during a time period, usually between 1 to 7 years. They didn't get any wages for their work, the employer paid for their subsistance and their passage to the country, but that also meant that he could restrict some of their activities, they weren't completely free. After their contract expired, they were allowed to stay in the country and sometimes they would get a small parcel of land. They were called the Indentured servitude.