Abstract: In 106 CE, the emperor Trajan conquered the Regnum Dacicum. His violent conquest caused radical discontinuity in the region's political structures, society, settlement patterns, economic development and religious practice. This posed a challenge unlike any the imperial government had faced before. Trajan therefore colonized Dacia extensively and transferred twenty thousand soldiers to the new province, creating a wholly new culture. I examine the processes by which imperial culture was established in this province 106--271 CE through an investigation of the limited literary sources supplemented by the archaeological and especially epigraphical evidence. On the basis of this evidence I show that complex processes of cultural formation were at work. This dissertation challenges established methodological paradigms. It questions the validity of the use of romanization as an interpretive model. The model of romanization formulated by Theodor Mommsen (1817--1903) is narrowly bilateral, taking account only of the two monolithic cultural blocks of Roman and 'native.' Secondly, my work reinterprets the evidence to emphasize the more complex and cosmopolitan nature of cultural formation. It is thus in line with the contemporary scholarship of archaeologists who are reexamining cultural change in the provinces. It emphasizes the avoidance of a Romanocentric viewpoint and the wider context of cultural formation. My thesis offers a micro-history of a province much-neglected by western scholars, but also expands the parameters of this debate by the inclusion of the epigraphical evidence. Comparison with other provinces on the northern frontier places imperial Dacia in its wider context. New cultures grew up all across the northern frontier between the first and the third centuries CE. The elements varied from camp to camp, town to town and province to province along the northern frontier. Although Dacia fits this pattern, it was also sui generis. The cultural mix was less beholden than usual to the provincial subjects. Dacia was the most cosmopolitan of Rome's northern provinces. This cosmopolitanism demonstrates the complex nature of new cultural formation. Multivalent elements which were themselves dynamic played a much stronger role than has previously been recognized.