The island of Kythera, in antiquity was called "Porfiris" (alias "Porfiroussa") and it was dedicated to Venus Kytheria/Heavenly Venus, whom the locals worshipped. According to Hesiodus, the goddess came to this island while she was on her way to Cyprus and her temple was built by the Phoenicians or, according to another tradition, by the Trojans.

The island's original name was Porfiroussa/Porfiris, because there was a significant quantity of the shell "porfira" on the coasts. The historians claim that the island was originally inhabited in 1,700 BC. The people of Kythera worshipped the goddess Kytheria (alias Kytheri Venus). In the temple of Kytheria, on the eastern part of the island, an armed wooden statue, one of the most ancient in Greece, was kept. After the Roman Rule, in 395 AD, the island came under Byzantine command, thriving during the 5th century. During the 7th century the Byzantine emperor Constantinos offered Kythera to the Pope until the period of Leon Isaurus, who gave the island to the Patriarchate of Constantinople. Markos Venieris conquered Kythera in 1207 and included the island in the Venetian acquisitions. During the Venetian Rule, the island was renamed "Tsirigo" and divided into the three provinces of Milopotamos, Agios Dimitrios and Kapsali. During the Venetian Rule, many pirates attacked and raided the few inhabitants of the island. On 28 June 1797, the French occupied Kythera. The French Rule became official with the signing of the treaty of Kamboformio, on 17 October 1797. On 21 May 1800, after signing the treaty of Constantinople, the independent "Ionian State" was founded under the Sultan's supervision. The Treaty of Paris, 5 November 1815, established the "United States of the Ionian Islands", thus validating the English Occupation. The people of Kythera offered significant help to the Greek fight against the Turkish Occupation. The best known fighters from Kythera were Georgios Mormoris and Kosmas Panaretos. On 21 May 1864, because of the popular demand for freedom and independence, the Ionian Islands were united with the rest of Greece. At the turn of the 20th century, the island of Kythera progressed economically and culturally. During the dictatorship of Metaxas, the island provided refuge for many politically exiled people, while the locals provided significant help to the resistance against the Germans.