As the sites which welcomed the prince, defied the enemy and regulated the passage of the merchant and traveller, the gateways and entrances (portae) of the eleventh-century west were markers and thresholds of community, power and sanctity. For the inhabitants of this gated world who took to the roads with the First Crusade, the portals of the cities and fortresses of the Near East represented important and recurring features in the landscape that they traversed. The gates that the crusaders encountered at the old Roman and Byzantine cities of Constantinople, Nicaea and Antioch were part of an urban architecture rendered on a scale few had ever experienced, evocative symbols of ancient authority and sacrality still bearing the marks of the triumphal military rulership of late antiquity by which they had originally been shaped. Nowhere, however, could the sight of gates have been as significant, and as eagerly anticipated, as at the holy city of Jerusalem itself.

Jerusalem and its sites were the central focus of Latin Christian devotion, and the city's urban geography was retraced in the imagination of believers as episodes from the life of Christ and the history of the Israelites were recited over the course of the liturgical year. The gates of Jerusalem and of its Temple are among the most common images in the Old Testament prophets and the Psalms.