Which best describes immigration to the united states between 1820 and 1850? between 1820 and 1850, nearly half of all european immigrants came from ireland, which differed from earlier waves. between 1820 and 1850, nearly a third of european immigrants came from the netherlands, which differed from earlier waves. between 1820 and 1850, most immigrants came from southern europe, specifically italy, which differed from earlier waves. between 1820 and 1850, most immigrants were brought from africa to become enslaved workers, which differed from earlier waves.