Dinarchus was a professional speechwriter active in Athens during the late 4th and early 3rd centuries BCE. A native of Corinth, he relocated to Athens to study rhetoric. As a resident foreigner, he was barred from speaking in court himself and instead earned his livelihood by composing forensic speeches for Athenian citizens to deliver. His career prospered under the Macedonian-supported administration of Demetrius of Phaleron.

Following the restoration of democracy in Athens in 307 BCE, Dinarchus was charged with collaboration, resulting in his exile and the confiscation of his property. He lived in exile for approximately fifteen years before being allowed to return to Athens around 292 BCE. He was a prolific writer, credited in antiquity with over 160 speeches. Only three of his orations survive in complete form, all stemming from the same major political scandal known as the Harpalus affair in 323 BCE. These speeches are Against Demosthenes, Against Aristogeiton, and Against Philocles. Scholars consider the authenticity of a fourth surviving speech doubtful.

Dinarchus holds historical significance as the last of the ten canonical Attic orators. His surviving works are important primary sources for understanding Athenian politics and law in the turbulent period after the death of Alexander the Great. According to ancient critics, his style was competent but heavily imitated greater orators like Demosthenes, leading some to view his work as derivative. Nonetheless, his speeches provide valuable insight into the practice of legal speechwriting and the functioning of Athenian courts under foreign influence.