The first part of this, citizenship is fairly simple: for the purposes of marriage, both parties had to be Roman citizens. Affectio maritalis is harder to pin down. It means both “marital affection” and “the intent to be married.” Generally, certain rituals of marriage would be performed, but they weren’t legally necessary. The partners only had to both be citizens and intend to be married.
This isn’t to say that all matches between two Roman citizens were called “marriage.” Sometimes there was simply too much of difference in status between two citizens to allow for a marriage. People did not always agree what constituted too much of a difference, but concern generally centered around situations where the male partner was of patrician status and the female was either a prostitute or a former slave.* These kinds of relationships had their own status and went by their own name: concubinage.
It’s important to remember that we’re talking about legal definitions here, not actual social practise. Although marriage in ancient Rome was of legal concern, people didn’t need a legal ceremony to get married. They only had to be legally permitted to marry and to consider themselves married. Imagine the drama if that were the case now.
* The idea that a woman might have a permanent, legal relationship with a man of lower status was unthinkable, and therefore also very complicated legally.
- Lefkowitz, Mary R. and Maureen B. Fant. Women’s Life in Greece and Rome: a Source Book in Translation, 1992.
- Rawson, Beryl. “Roman Concubinage and other De Facto Marriages.” Transactions of the American Philological Association 104 (1974).
- Treggari, Susan. “Concubinae.” Papers of the British School at Rome 49 (1981).