The ancient writers make mention of Nauplion, as an important city, that took part in the Argonautic Expedition and the Trojan war. In the latter, there also parti­cipated Palamedes the sage, son to the fifth founder of the city, called also Nau­plius. This Palamedes was falsely accused by Odysses of being a traitor and was murdered at Troy, as we learn from the lost tragedy by Euripides, bearing his name.

Until the 7th century B.C. Nauplion was a small independent city, that had deve­loped along with Mycenae and Argos. Du­ring the second Messenian war (middle of 7th century B.C.) the Nauplians had al1ied with Sparta, Argos' opponent. This was the reason that the king of Argos Democrati­das occupied and devastated Nauplion du­ring this war. The Nauplians moved to Messenia then and the city became Argos' naval yard and sea port.

It was in the 11th century that Nauplion rose up again and started acquiring histo­rical importance. A1ready in the 9th century it had acquired its own diocese that was under the metropolis of Corinth, and its first bishop was St. Peter of Argos. The By­zantine emperors discerned the importance and the mercanti1e capabi1ities of the city's position and so they reinforced it.

In 1180 A.D., the Byzantine Emperor Ma­nuel Comnenos appointed Theodore Sgou­ros, a rich Nauplian, as the ruler of Nau­ρΙίοn. His son, Leo Sgouros, turned Nau­plion into an important centre. He fought against the invading crusaders, Montfer­rat, Champlitte and Villehardouin. The lat­ter occupied the city taking it from Theo­dore Doukas Comnenos, Sgouros' Succes­sor. In 1212 Villehardouin conceded the city to Otho de la Roche Master of Athens. The city remained under the administration of the French dukes of Athens for appro­ximately a hundred years and was fortified by them. Subsequently it came into Vene­tian hands.

In the years 1396, 1463, 1502 the Turkish attacks were successfully repelled. Ιn 1540 under a treaty the Venetians gave Nauplion over to the Turks. Ιn 1686 Francesco Moro­sini the venetian field marshal, after a 10ng siege occupied Nauplion and started forti­fying it. Nauplion then became the capital of the prefecture of Romania and was cal­led Napoli di Romania. The general Augu­stine Sagredo and the prefect Jeronymus Delphinus completed the fortifying works of the city that had now become

...Morea's (J) boast and crown

and everyone looked upon it with respect.

In 1715, after a 10ng siege, Nauplion came into Turkish hands. The besieger, Daout Pasha, gained entrance to the city, after the treason of Sala, a French artillery colonel fighting at Palamidi. In Αpril 1821 the Greeks started a siege of the city.

On November 30, 1822 Pala­midi was taken by Staikos Staikopoulos and a little later the city was handed over to Kolokotronis, a greek hero and leader of the 1821 revolution. At the beginning of 1823 Nauplion was appointed the capital of the Liberation war and the government had its seat there. Then Greeks from all the parts of the country started swarming in. Α vivid picture of the time, with its confusion of different customs and dialects is given in «The Babylonia» by Byzantios. During the civil conflicts the city was the battlefield of the dissenting groups of the Administrative Committee and the Parliamentary one.
Ioannis Kapodistria, after the libera­tion, arrived at Nauplion as the Governor of Greece on January 8, 1828. It was here that he set out the plans of the development of the country and it was here that he found a tragic death on September 27, 1831, murdered by two members of the Mavromichalis family, as he was entering St. Spyridon's church. The 4th National Assembly (1832) approved of the choice of Otho as King of Greece, who came to Nauplion οη January 25, 1833. On December 1, 1834 the capital was transferred in Athens.