The book progresses through three key sections, starting with a theoretical framework that defines core concepts. It then analyzes specific case studies from different continents and historical periods, illustrating the varied impacts of border shifts. Finally, it explores contemporary implications, scrutinizing how current border policies and geopolitical tensions continue to fuel migration flows. This approach provides a comprehensive understanding of the complex interplay between borders and migration, making it a valuable resource for policymakers, historians, and anyone interested in understanding the root causes of contemporary migration patterns.