Without a special historical presence in the Medieval Ages, it was thought that Hydra was unimportant until the first post Byzantine years when the island followed the destiny of the major cities nearby on the Peloponnese, which it belonged to. Politically and culturally the nearby Dhokos Island, belonged to Hydra throughout these centuries as it still does today.
Most areas of Greece were in turmoil because of war during these centuries. This combined with the outbreak of piracy in the Mediterranean, contributed to further settlement on the island. Throughout this period several Greek families moved to Hydra. From Epirus the Lazarou, Zerva, Kokini and Koundouriotis families; from Kythnos the Barou, Rafalia, Nega, Ghika and Gouma families; from Vourla of Smyrna, the Giakoumaki and Tombazis families; from Euboea the Vokos, Miaoulis, Kriezis and Boudouris families; from Kranidi the Tsamados family; from Genova Kiosses, Sahinis and Sachtouris; the Epidaurus family, the Economou family and others from all over Greece.
Further settlement occurred during the next Venetian-Turkish war (1700 - 1715), the Russian-Turkish war (1768 - 1774) and also during the Greek revolution (1821), which moulded the social and cultural evolution of Hydra. Thus, Argosaronikus, insignificant until this period, numbered 27,000 inhabitants. This demographic explosion had positive and negative consequences regarding social progress. The most positive being, were the development of trade and the rapid progress of shipping.
In 1802 the governmental system of the island changed when Kapoudan Pashas' favourite George Dimas Voulgaris, the chief commander of the Turkish flag ship, was sent to Hydra. Voulgaris was
appointed by the sultan as Kotzabasis and supervisor (Naziris) of Hydra, Poros and Spetses in order to regain peace and order on the islands. His prudence as well as Ottoman favour, contributed to a
well-governed island. The period of economical prosperity, the control of piracy and internal peace, which followed the years of Voulgaris' rule, gave the Hydrians the opportunity to organize their
society as they wished.
The constant fights against pirates changed them from farmers and shepherds into bold seaman. On the eve of the Greek National Independence War the island was on alert. Hydra had 120 ships ready for war, 45,000dwt, 5,400 men and 2,400 cannons.
Many Hydrians, some of them eminent persons within the island's society, joined the Filiki Etairia (Society of the Friends, the secret Greek independence organization) in around 1818. The
considerable amount of 130,000 distila (about 40,000 pounds sterling) was raised by Hydra's leaders and the epic rise of the island began.
Hydra bore the brunt of the war and became the focal point for Greek naval forces. The successive victories during sea battles and the dominance of Hydrian heros, served to compose the islands historical picture. Koundouriotis, Tombazis, Kriezis, Sahtouris, Tsamados, Voudouris, Economou, Pipinos, Gionis, Robotsis, Vatikiotis, Gelis, Skourtis, Methenitis, Vatsaxis, Sahinis and Andreas Miaoulis with his imperious character, each contributed to the revolution in his own way and raised the status of this small, Greek piece of land throughout Europe.
In 1822 Andreas Miaoulis took over the leadership of the Hydrian fleet, since then the island bares the palm of the sea battles. The achievement of the objective of Hydra and Greece in general soon became apparent. In 1827 at Navarino's sea battle, the united fleets of England, France and Russia restricted the Ottomans ambitions and in 1830 forced them, with London's Protocol, to recognize the independence of the Greek state.
The first governor, Ioannis Kapodistirias began the difficult process of restoring peace after the state of emergency. Hydra of course wasn't an exception to the rule. The military expenditure had been a drain on the island's resources. Furthermore, relations between liberal Hydrians and the Governor, with his restorative program, deteriorated because Kapodistirias objected to paying compensation for damages to the islanders. The inevitable rupture between the two sides resulted in opposition confrontation between them especially through the press. Hydrians and other dissatisfied islanders from the Aegean sea, people of Poros, Mykonos, Syros, Naxos, Andros and Paros fought hard against Kapodistirias which led to rebellion against him when ships of the Greek fleet were set on fire.
On The 1st of August 1831, at the port of Poros, Andreas Miaoulis destroyed the corvettes, "Hydra" and "Spetses" and the frigate "Hellas". These tragic events reached their climax when Governor Kapodistirias, was murdered by George and Constantinos Mavromihalis on the 27th September 1831 at Nafplio.
In spite of the absence of Kapodistiras the situation didn't improve. Unfavourable economic circumstances, unemployment of ships crews, the revolutionary changes in navigation from sail to steam
wrought by the appearance of the first steam ships in the middle of that century, contributed to an unsettled situation. The Hydrians despaired as they resisted the innovative changes and many of
them decided to leave the island to seek better fortune in capital cities. The new "deus ex machina" sponge fishing, failed to provide sufficient incentive for them to stay. Athens and Piraeus became
their new homes.
However, the historical social and political stress does not diminish the Hydra's proud contribution to the Greek nation. This small island has presented Greece with one president, five prime ministers and numerous cabinet ministers. In order of premiership, the following Hydrians have governed Greece:
•George Koundouriotis Prime Minister and Minister of Shipping during the reign of King Otto - March to October 1844.
•Antonios Kriezis Prime Minister during the reign of King Otto - December 1849 to May 1854
•Dimitrious Voulgaris Prime Minister of Greece 7 times.
•Athanasios Miaoulis Prime Minister for Greece 3 times.
•Petros Vougaris Prime Minister of Greece - 1945.
Another great Hydrian of modern Greece, was Pavlos Koundouiriotis, the inspired Admiral of the Greek fleet, victorious at sea battles during the Balkan and First World War. In 1923 after the removal of King George II from the throne, Koundouriotis served as the provisional governor of Greece for 1 year. In 1924 the national assembly elected him the first President of the Greek Democracy.