Author
- Nikolaus von Dinkelsbühl1
- Notre-Dame de Chartres1
- Onasander1
- Order of the Immaculate Conception1
- Orderic Vitalis1
- Osbern of Gloucester1
- Palazzo degli Anziani1
- Panormitanus1
- Paschal II1
- Paschasius Radbertus1
- Paschualis Bernardus1
- Patrick Graham, 1st Lord Graham1
- Paul of Venice1
- Paul the Deacon1
- Pedro de Serra1
- Pere Marsili1
- Pere Rossell1
- Peter Damian1
- Peter Olivi1
- Peter of Bergamo1