Who was the last king of Sparta in antiquity?

Nabis is commonly identified as the last king of Sparta in antiquity. He ruled during the early second century BCE and was killed in 192 BCE, when Sparta remained entangled in conflicts among Greek states and Rome.

Nabis used the royal title and pursued reforms that strengthened his position in Laconia. Ancient sources hostile to him portray him as a tyrant, while modern historians treat those accounts cautiously because they were written by political opponents and later authors.

In 195 BCE, a Roman-led coalition attacked Nabis after disputes involving Argos and Spartan expansion. He survived that war but was assassinated by Aetolian conspirators. After his death, Sparta’s political independence continued to shrink, and the city eventually became part of the Roman sphere in Greece.