Gaius or Caius Plinius Secundus, (23 CE – August 25, 79 CE), better known as Pliny the Elder, was an ancient author, naturalist and naval and military commander of some importance who wrote Naturalis Historia (Natural History). Natural History consists of thirty-seven books including all that the Romans knew about the natural world in the fields of cosmology, astronomy, geography, zoology, botany, mineralogy, medicine, metallurgy, and agriculture.
Pliny based his work on earlier Greek authors. When these Greek works were lost, Natural History became the primary educational text of the medieval period.
Today it serves as a primary source for information on life in the Roman period.