Cato the Elder, also known as Marcus Porcius CATO, was an ancient Roman historian who lived in the 2nd century BC. He is best known for his writings on the history of Rome and its government. Livy, or Titus Livius, was another ancient Roman historian who lived in the 1st century BC. He wrote a monumental history of Rome from its foundation to his own time. Pliny the Elder, or Gaius Plinius Secundus, was an ancient Roman author, naturalist, and philosopher who lived in the 1st century AD. He wrote a number of works on natural history, including the Naturalis Historia, which is one of the most important works of the Roman Empire. Ovid, or Publius Ovidius Naso, was an ancient Roman poet who lived in the 1st century BC. He is best known for his works on love and mythology, such as the Metamorphoses.