The island's name means "island of women". It is possible, therefore, that Naissaar is the island the chronicle of Adam of Bremen mentioned around 1075 under the name "Terra Feminarum". Estonian Swedish fishermen were well-established on the island by the 15th Century, and the Swedes erected a small fortress there in 1705 during the Great Northern War. After the war Estonia became part of the Russian Empire. The Tsar had a new fortress, with five bastions, built in 1720, for the defense of Tallinn and St. Petersburg.
An epic single-ship action took place off the north end of the island on 23 June [O.S. 11 June] 1808 when the 14-gun Russian cutter Opyt put up an heroic though ultimately unsuccessful fight against the British 44-gun frigate HMS Salsette.
In 1850 the island's population was 155 people and by 1858 it had grown to 188, most of whom were Estonian Swedes. Between 1853 and 1856 the inhabitants built a new chapel that was part of the Swedish parish of St. Michael in Tallinn.
In the early twentieth century, Russia began the process of a modernization of its fortifications in the Gulf of Finland. However, the outbreak of the First World War stopped the planned improvements for Naissaar. Still, in 1914 the Russians opened a narrow-gauge railway line, with a total trackage of 37.7km.
World War I
The Russians built a new fort during the First World War. Estonia acquired some autonomy in April 1917 by a decree of the Russian provisional government, though Estonia remained under the suzerainty of the Russian Empire. However, after the October Revolutions the Bolshevik rebels suspended Estonia's provisional government, the Maapäev.
In December 1917, a group of Russian sailors commandeered Naissaar and proclaimed an independent "socialist republic", known as the Soviet Republic of Soldiers and Fortress-Builders of Nargen, under the leadership of Stepan Petrichenko. The Russian
