- Perocti, Maruccio1
- Perpetual calendars1
- Persius1
- Peter Lombard, Bishop of Paris, approximately 1100-11601
- Peter Martyr, Saint, approximately 1205-12521
- Petrarca, Francesco, 1304-13741
- Petrini, Mattea1
- Petronibus, Ludovicus Salimbeni de1
- Phaedra (Greek mythological character)1
- Philip III, King of Spain, 1578-16211
- Philip IV, King of Spain, 1605-16651
- Philosophers, Ancient1
- Physical appearance of Jesus Christ1
- Physical sciences1
- Physics1
- Physics (Aristotle)1
- Piccinino, Nicolo, -14441
- Piccolomini d'Aragona, Antonio di Nanni Todeschini, Duke of Amalfi1
- Piccolomini di Castiglia e d'Aragona, Giacomo di Nanni Todeschini1
- Piccolomini, Agnes1