[VinL]

With no disrespect, which religion held that a interracial couple could not marry?

[Jack Black]

Various racist Christian sects oppose integration. As group they are usually referred to as "Identity Christians". Here is a link to the Wikipedia article about them.

Until the 1970s the Mormon Church held a very dim view of Blacks and forbid inter-marraiage or membership of Blacks in their church. Here is the Wikipedia article "Black People in Mormon Doctrine".

As in most relgiions there are various splinter groups that don't agree with the latest politically expedient updates to the chuch teachings, and break off and form schismatic sects. There are several well known sects that still do not agree with the poltically expedient decision to end Mormon support for Polygamy, made by the LDS leadership in 1890 to speed the acceptance of Utah into the USA as a State.

The Southern Baptists were founded (schism) to support the institution of black slavery.

[Sherman Logan]

Several family members were involved with Christian Identity and other Anglo-Israelite groups. There are, or at least were, a whole bunch of these tiny groups. Thankfully, my family members have all jumped ship at this point.

I’m not clear on the dates, but Southern Baptists opposed interracial marriage at least into the 70s or 80s, and Bob Jones university didn’t give up its opposition to interracial dating till 2000.

I’m not sure how to go about proving it, but I’m reasonably sure most southern churches opposed interracial marriage through at least the 60s and 70s.

Entirely without any scriptural backing, BTW. Racism is alien to the Bible.