The church later called the Old Minster was founded in Anglo-Saxon Winchester, traditionally in 648 under King Cenwalh of Wessex, though the precise early chronology depends partly on later sources. By the later seventh century it served as the West Saxon cathedral. Expansion accompanied Winchester’s rise as a royal and ecclesiastical center. Kings, bishops, and saints were buried there, and the cult of Saint Swithun drew pilgrims after his remains were translated into an enlarged church in the tenth century.

The Old Minster stood close to the New Minster, founded around 901, creating a crowded sacred precinct beside royal buildings. Reformers in the tenth century established Benedictine observance and rebuilt parts of the cathedral. After the Norman Conquest, Bishop Walkelin began an immense Romanesque replacement in 1079. The new cathedral was consecrated in 1093, and the Old Minster was then demolished. Its stone was reused, graves were disturbed or transferred, and the new church absorbed its cathedral, monastic, and commemorative functions.

Winchester Cathedral retains major Norman transepts, crypt, and structural fabric, but later medieval campaigns transformed much of its appearance. The east end was extended, and fourteenth- and fifteenth-century builders recased the long Norman nave in Perpendicular Gothic form. Chantries, screens, stalls, glass, and monuments accumulated around Saint Swithun’s shrine and royal burials. The Reformation destroyed the shrine and altered monastic worship, while parliamentary soldiers damaged glass, tombs, and furnishings during the English Civil War.

Waterlogged foundations threatened the east end in the early twentieth century. Divers, most famously William Walker, worked beneath the walls to remove peat and insert support before engineers underpinned the structure with concrete. This rescue preserved medieval fabric through major modern intervention. Archaeologists excavated the Old Minster between the 1960s and 1980s, recovering incomplete plans, graves, and evidence of successive buildings. Its footprint is now marked in the cathedral close; visitors see an interpreted archaeological site, not standing reconstruction of the Anglo-Saxon church.

The cathedral remains an active Anglican church and a complex monument containing original, altered, restored, and reconstructed elements. Mortuary chests preserve commingled remains traditionally linked with early kings and bishops, now studied with modern scientific care rather than accepted as simple individual identifications. The Old Minster outline and the surviving cathedral should be read together: one records a vanished Anglo-Saxon institution through archaeology, while the other embodies Norman replacement, Gothic transformation, religious upheaval, structural rescue, and continuing worship on the same sacred center.