Definition: Pliny was the name of two Roman writers. The first Pliny, Pliny the Elder, was born in A.D. 23 in Como. Pliny was in command of the fleet stationed at Misenum, under Titus, when the volcano on Vesuvius erupted in A.D. 79. Pliny wrote the Natural History. Pliny the Elder's adopted son, Gaius Plinius Caecilius Secundus wrote speeches which have been lost. We have a collection of Pliny the Younger's letters.