Speyer Cathedral, officially the Imperial Cathedral Basilica of the Assumption and St Stephen, in Latin: Domus sanctae Mariae Spirae in Speyer, Germany, is the seat of the Roman Catholic Bishop of Speyer and is suffragan to the Roman Catholic Archdiocese of Bamberg. The cathedral, which is dedicated to St. Mary, patron saint of Speyer and St. Stephen is generally known as the Kaiserdom zu Speyer. Pope Pius XI raised Speyer Cathedral to the rank of a minor basilica of the Roman Catholic Church in 1925.

Speyer, historically known in English as Spires, is a city in Rhineland-Palatinate in Germany with approximately 50,000 inhabitants. Located on the left bank of the river Rhine, Speyer lies 25 km south of Ludwigshafen and Mannheim, and 21 km south-west of Heidelberg. Founded by the Romans, it is one of Germany's oldest cities. Speyer Cathedral, a number of other churches, and the Altpörtel dominate the Speyer landscape. In the cathedral, beneath the high altar, are the tombs of eight Holy Roman Emperors and German kings.