This dissertation argues that the increase of upland settlement, noted in the archaeological record for the middle Byzantine period (seventh through thirteenth centuries) on Mount Latros and Mount Mykale, should be associated with the period between 961 and 1081. Settlements in this period were characterized by a mountain resilience rooted in security from external threats, diverse economic opportunity, and monastic mountain leadership. The usual association obscures a complicated and often contradictory relationship between mountains and war. In fact, increased settlement was enabled by a new interconnectivity between mountain and plain defined by imperial control of territory in the Maeander valley and the newly ascendant monastery on each mountain. I deploy a new method for mapping the border descriptions or periorismoi within the Praktikon of Adam, a survey document produced in 1073 for the donation of an imperial property. Landscapes in the mountains and in the wider Maeander valley truly come into focus when these descriptions are mapped and compared with the archaeological survey data. The dissertation is divided between Part 1: The Mountains, comprising the first two chapters, and Part 2: The Maeander Plain, comprising the second two chapters. In Part 1, I show how the two newly founded monasteries of Stylos and Hiera Xerochoraphion transformed the marginal mountain landscape into a new center of authority. The isolation, which aided in the construction of authority vis-à-vis the hagiographical traditions of their founders’ eremitic virtues, also necessitated the investment in a network of roads across each mountain which alleviated the isolation of other mountain settlements. In Part 2, I show how the cities, whose bishops often considered any monastery on the mountain under their authority, were sidelined by the accumulation of imperial territory in the Maeander valley. Imperial estates benefited the most from the economic and demographic recovery in the Maeander valley and the wider Byzantine Empire beginning in the tenth and eleventh centuries.