A gemengd huwelijk is a mixed marriage. The term typically refers to two people with different religions, but is sometimes also used for two people of different racial backgrounds.
Until recently, many churches would not perform a mixed marriage ceremony and required the other party to convert and promise to raise all their children in that church’s faith. A civil marriage before the court was an alternative for couples who did not want to convert. Some couples chose to raise the boys in the father’s faith and the girls in the mother’s faith.