Columbia subject headings:
Church history--Middle Ages, 600-1500.
Conversion--Christianity--History--Middle Ages, 600-1500.
Europe--Church history--600-1500.
Evangelistic work--History--Middle Ages, 600-1500.
Missions--History--Middle Ages, 600-1500.
Harvard subject headings:
Church history--Middle Ages, 600-1500
Church history--Middle Ages, 600-1500--Congresses.
Conversion--Christianity--History--Middle Ages, 600-1500--Congresses.
Europe--Church history--600-1500--Congresses.
Evangelistic work--History--Middle Ages, 600-1500--Congresses.
Missions--History--Middle Ages, 600-1500--Congresses.
Princeton subject headings:
Church history--Middle Ages, 600-1500.
Conversion--Christianity--History--To 1500.
Evangelistic work--History--To 1500.