Pope Gregory's letter-bearers

"With the Lombards invading Italy, and Slavs invading Illyria, and very active slave-dealers at work, the number of men and women who reached Rome and carried a papal letter, to sort out a legal or personal problem at home, is quite surprsing, considering the slowness and the very real dangers of often long journeys in boats or on horseback. ... [T]hey came from all over the civilized world, many briefly appearing on the stage, their mission quite often not reported later on."--Cover, p. [4].