Political Weirdos

I'm not going to bother to explore what the pre-2018 laws were, but even for a lot of the laws where underage people are still allowed to marry, 14 is still younger than age of marriage in general.

And this is separate from age of consent. The four states that have no specified minimum marriage age have age of consent at 16 or 18, so technically you can be married but not having sex. Being a child spouse even without the sex part is screwed up, so it's a somewhat related, but different concern to this discussion.

Incidentally 'technically' is doing a lot of heavy lifting there. Someone under the age of 18 needs at least parental approval in those four states, and even in the worst of those cases if someone is under 15, a judge has to get involved and explicitly approve the marriage as well as parents. So again, a 14 year old getting married? In theory possible but unlikely even in the few states where it is technically legal.

In short, yes, it was broadly illegal, with some states giving green light at 16, and under more select circumstances earlier (I see the wikipedia table goes as low as '13' 'by age', but unrestricted only goes down to 16. I don't quite understand what the 'by age' and 'by authority' columns even mean, but I'll assume 'unrestricted' is at least where you don't need to find a weird loophole.