Algerian diaspora is examined from reasons based on military service, asylum seeking, captivity and imprisonment, travel for commerce, study, or religious purpose, and labor migration. The author reviews these factors and provides an in-depth analysis of the results of these crossings, from problematic efforts to secure external support for political projects through building interfaith dialogue and the exploration of new ideas to the emergence of new communities. He also investigates the return of border crossers to Algeria and the challenges they face in adapting to new environments, whether negotiating alliances, engaging in dialogue, or simply seeking legal acceptance. He concludes with a discussion of the last few decades of Algerian history. He explores how Algerian intellectuals operated outside of the country's borders, spurred on by the rise of Islamism as well as by freer dialogues with Western powers, specifically Britain and the United States. The result is an exciting new history of Algeria that demonstrates just how much its citizens' engagement with other societies has transformed the country.