In Greek mythology, Tantalus was a son of Thyestes and a prince of southern Argolis. He was killed along with his brother Pleisthenes, by Thyestes's brother Atreus. Atreus killed his nephews because Thyestes seduced his wife, Aerope. Atreus was the king of Mycenae, and Thyestes ruled the south of Argolis.
Other characters named Tantalus
The name Tantalus was common in Tantalus's family. The first Tantalus, son of Zeus, is the most famous. He was favored by the gods but sacrificed his son Pelops (Thyestes's father) to the Olympians, who hated human sacrifice. The gods killed Tantalus and brought Pelops back to life. Pelops had a brother named Broteas who had a son named Tantalus. Tantalus II was killed by Agamemnon, who married his wife, Clytaemnestra.
References
Tantalus (son of Thyestes) Wikipedia(Text) CC BY-SA