The hat was actually a traditional camauro, a fur-trimmed cap that popes used to wear against the cold. Today’s temperature was around 9 degrees Celsius (48 F).
The 15,000 pilgrims present in St. Peter’s Square applauded enthusiastically on seeing the red-hatted Holy Father arrive in a white jeep.
Because of the great number of pilgrims, the audience was not held in the cozy Paul VI Hall but in the open air.
Camauros date back to the 12th century. They fell into disuse, until the papacy of John XXIII. After that pontificate it fell into disuse again — until today, to the surprise of observers.
Benedict XVI removed his camauro at the start of the audience.