‘Brother-Sister’ Marriage in Roman Egypt: a Curiosity of Humankind or a Widespread Family Strategy?

Abstract

Scholars over the last few decades have been unable to find a convincing explanation for the widespread practice of brother-sister marriage among the common people in Roman Egypt, a social practice seemingly disregarding one of the most fundamental taboos. This paper now argues that these ‘incestuous’ marriages were in fact marriages between a biological child and an adopted one, a practice documented also for other parts of the Eastern Mediterranean. Due to the severe mortality regime before the demographic transition, up to 30 per cent of all fathers did not have a male heir, and therefore adopting the son-in-law was a common succession and inheritance strategy in many pre-modern societies.