Tacitus was a Roman historian and senator who lived from around 56 to 120 AD. He is best known for his works, including the Annals and the Histories, which provide a detailed account of the Roman Empire during the first century. His writings are valued for their insights into the political and social life of the time. Tacitus is recognized for his critical approach to history, often emphasizing moral lessons and the impact of power on society. His style is characterized by brevity and a focus on significant events, making his works essential for understanding the complexities of Roman history and governance.