Former Owner
- Robert Brodhead Honeyman1
- Robert Dallas1
- Robert Dechert1
- Robert Devereux, 2nd Earl of Essex1
- Robert Dudley, 1st Earl of Leicester1
- Robert Lehman1
- Robert Samuel Turner1
- Robert Treswell1
- Robert Walker1
- Robert de Mol1
- Roderick Terry1
- Rodrigo de Abejos1
- Roger North, 2nd Baron North1
- Royal Monastery of Saint Mary of Guadalupe1
- Rudolf Busch1
- Rudolf Hofmeister1
- Rui Garcia1
- Ruth E. Adomeit1
- Sabina Sopheija Behren1
- Sam Fogg Rare Books & Manuscripts1