Leotychidas II (Ancient Greek: Λεωτυχίδας; Doric: Λατυχίδας Latychidas; c. 545 – c. 469 BC) was king of Sparta from 491–476 BC, alongside Cleomenes I and later Leonidas I and Pleistarchus. He led Spartan forces during the Persian Wars from 490–478 BC.
Born in Sparta around 545 BC, Leotychidas was a descendant of the Royal House of the Eurypontids (through Menamus, Agesilaus, Hippocratides, Leotychides, Anaxilaus, Archidamos, Anaxandridas I and Theopompus) and came to power in 491 BC with the help of the Agiad King Cleomenes I by challenging the legitimacy of the birth of Demaratus for the Eurypontid throne of Sparta. Later that year, he joined Cleomenes's second expedition to Aegina, where ten hostages were seized and given to Athens. However, after Cleomenes's death in 488 BC, Leotychidas was almost surrendered to Aegina.
