[Sci Fi Guy]

Are either or both of them Catholic?

I believe that one must be, and both must promise to raise their kids as catholics.

[Bonaparte]

My understanding is that they must also undergo a church-approved nuptial training and that the non-Catholic must also promise to practice Catholicism, in addition to raising the children to be Catholic.

However, a bishop can make an exception to any or all church requirements, and in the US frequently does. IOW, the catechism as concerning Catholic marriage has become an optional afterthought.

[Restorer]

Thank you, that was what I thought. Although with everything going on in the Catholic Church today, perhaps a Jew and a Muslim being married in a Catholic ceremony wouldn't be so strange after all!