Gaius Popillius Laenas

Gaius Popillius Laenas (also spelled Popilius) was one of the two Roman consuls in 172 and 158 BC.

He was sent as an envoy to prevent a war between Antiochus IV Epiphanes of the Kingdom of Syria and Egypt. On being confronted with the Roman demands that he abort his attack on Alexandria, Antiochus played for time; Popillius Laenas is supposed to have drawn a circle around the king in the sand with his cane, and ordered him not to move out of it until a firm answer had been given. The Syrians withdrew.

Some sources for this story are Cicero, Philippics 8.8, and Livy, Ab Urbe condita 45.15.