The tenth century was a period of greater interaction between Byzantium, its immediate neighbours, and further afield. This can certainly be seen in the development and immediate rise of marital alliances, both in and out of the Byzantine Empire. Prior to this, though women of noble birth had on occasion been married into the imperial family of Byzantium – one example being the marriage of Theodora, the Khazar princess, to Justinian II on his re-accession - there had been very little in terms of marrying elite and imperial Byzantine women to foreign rulers. The oft-quoted De Administrando Imperio, famously compiled by Constantine VII Porphyrogennetos in the tenth century, claims that this was the edict of Constantine the Great: those who were alien to the Romans, and especially those who were unbaptised, should never be allied with by marriage. Yet, even as this was compiled – or perhaps because, inter-marriage with foreign houses increased exponentially, leading to a growth in global networks across this period. The number of marriages could even have been higher, as this period is peppered by betrothal contracts that were arranged but never fulfilled, due to unexpected deaths and late break-downs in negotiations. In this paper therefore, I will discuss why the constraints around the marriage contracts of imperial and elite progeny were loosened in the tenth century, and what the global impact of this increase in marriage alliances may have been.

This thesis demonstrates that the emperor Augustus (31 BC to AD 14) did encourage and instigate marriage-alliances between Roman client kings, as suggested by the sources. Analysis of the marriage-alliances formed before Augustus’ reign reveals a number of characteristics that did not apply to many of the marriage-alliances formed during Augustus’ reign and beyond. New or modified characteristics have assisted in the determination of which marriage-alliances were arranged by the emperor. Furthermore, this thesis also assesses the possible aims that compelled Augustus to arrange or encourage these marriages, how this policy complied with the emperor’s other beliefs and policies regarding marriage in general, and whether his policy was continued by his successors. Finally the repercussions and problems that arose from binding the client kings together through intermarriage are examined and the policy assessed in terms of success or failure. The study of Augustus’ policy of intermarriage between client kings also illuminates the nature and role of client kings within the framework of the principate and shed further light on their relationship with the emperor.

À Byzance, les conceptions et les pratiques relatives au mariage n’étaient pas fixes, et les principes liés à la contraction d’une union ainsi qu’à la manière de la constituer ont varié jusqu’à la fin du ixe siècle. Dans cet article, le cadre juridique alors en vigueur qui valide la vie maritale, est brièvement abordé. Il est montré que les auteurs, en particulier ceux des textes hagiographiques, évitaient de se rapporter à la façon dont les mariages étaient contractés, dans la mesure où les Byzantins ne recherchaient pas – pour autant qu’il était permis – la bénédiction de l’Église, considérant la fondation d’une nouvelle famille comme une affaire qui concernait exclusivement la société et l’État.

This paper aims to discuss the importance of diplomacy as a major factor in the survival of the Byzantine Empire for 1123 years – from the inauguration of the empire’s capital, Constantinople on May 11, 330 CE, until the fall of Constantinople and, consequently, the Byzantine Empire to the hands of the Ottomans on May 29, 1453. It was one of the longest lasting social organisations in history. Byzantium survived through adaptation and diplomacy. The backbone of Byzantium’s longevity was its administration, which managed to adapt to frequent changes of rulers, and ongoing crises on its borders. With a very limited military force and ongoing crises on its borders, diplomacy was the key for the empire’s survival.

Approaching warfare in pre-modern states from the perspective of risk reduction, we see that royal marriage was one strategy rulers used to reduce the probability that they would lose a war. Judicious marriage exchanges intensified and prolonged patron-client relations between rulers or between rulers and societal elites. Clientelism could affect the size and composition of their armies. The more warriors and troops one could field, the greater the chance of not losing a war (Otterbein 2004; LeBlanc 2006). Examination of eight pre-modern states suggests that their rulers used the same patterns of wife exchange even though most states developed independently. Marriage secured long-term patron-client relationships, which they used to support their militaryefforts.Whenrulersmarriedtheir kinormarriedthemtorulersoutsidethe system (“foreigners”), they did not gain military support. Analysis of these marriagemilitary patterns reveals several characteristics of pre-modern states. First, marriage alliances helped rulers form networks of support that helped them win wars. Therefore, marriage—and by extension, royal women—is a key component to the study of warfare and a critical mechanism of network formation, as Blanton et al. (1996) write. Second, alliances were based on a different organizing principle from Levi-Strauss’ tribal societies, for rulers selected main wives (for themselves or their kin) based on relative rank rather than particular kinship ties. Third, marriage alliance reveals an important difference between alliance and patron-client relationships, a distinction that is often blurred in the archaeological literature.