Historically, the area was known as Krommyona, possibly named after its onion production (“krommyo” in Greek) or the ancient deity Poseidon Krommo. It was a significant point of interest among Greek city-states before becoming part of Megara and later Corinth . Today, Agioi Theodoroi is part of the Loutraki-Perachora-Agioi Theodoroi municipality .