According to arceological finds, the territory of Saaremaa has been inhabited at least five thousand years.
Thanks to its favourable climatic conditions and geographic isolation Saaremaa was one of the most densely populated areas in Estonia before the beginning of occupation of Estonia by German crusaders (at the beginning of the 13th century).
In Scandinavian sagas of the 8th - 10th centuries Saaremaa was mentioned as Eysysla. In old German and Russian sources its name was Oesel.
Due to its geographical location between the East and West, the territory of Saaremaa as well as the whole Estonia was under the rule of different countries for seven centuries: in January 1227 the Teutonic Knights brought an army of 20,000 across the frozen sea and established German rule, which would last, despite frequent rebellions, until 1559.
The next 90 years would see five different conquerors, first the Danes, then the Swedes to be followed by another Danish invasion, then the Russians and finally the Swedes again in 1645. The Swedes lost their Baltic possessions to the Russians in 1710.
The Tsarist Empire came to an end in 1917, but Saaremaa was immediately reoccupied by German troops who left in November 1918. After that Estonia got his first Republic till 1940.
The devastation of World War II, the deportations to Germany and Russia and the "boat exodus" to Sweden led to a reduction in the population of more than 30% from 56,000 in 1939 to 38,000 in 1945; it has stayed around this level ever since.
At the beginning of the 20th century, there were approximately 60,000 ingabitants in Saaremaa, about 4000 of them lived in Kuressaare. It was a typical agrarian region with a very high population density. That is why many islanders were forced to make their way to the mainland or even into other countries.
A part of the population expressed their dissatisfaction by apostizing from the Lutheran Church to Orthodoxy in the middle of the 19th century. Quite a number of people were active in a working - class revolutionary movement at the beginning of the 20th century.
The reforms that took place during the second half of the 19th century livened up the economic life in Saaremaa and facilitated the progress of entrepreeurship.
Important landmarks in the district's development were the opening of ship lines to Riga and St. Petersburg in 1858, and the beginning of regular ferry - boat traffic between the mainland and the island of Muhu in 1888, construction of the Roomassaare Port in 1894, the completion of the land bridge between Saaremaa and Muhu in 1896, the organization of telegraph communication between Kuressaare and Pärnu in 1875 and the launch of the first electric power plant in 1912.
The cooperative movement of islanders started to develop: the first farmer`s association was founded in 1899: the dairy cooperative at Valjala in 1912, the consumers cooperative at Tornimäe in 1905: the savings and loan association at Kuressaare in 1911. Progress was made in education and culture. Many former manor houses were turned into schools and tens of new modern schoolhouses were built. In the 1930s there were 80 state primary schools and a Gymnasium in Saaremaa. The trades necessary for the developmend of the district's economy were taught at Kuressaare Nautical School (founded in 1891), Industrial School (1922), Kõljala agricultural School (1919) and Karja School of Domestic Economy (1929).
According to an ancient tradition the islanders enriched their diet with fish, though only 2 per cent of them were professional fishermen.
The events of the summer of 1940 interrupted everything that had been achieved: in June 1940, as a consequence of the Molotov-Ribbentrop pact, signed on August 23, 1939, Soviet Army occupied Estonia and in August the country was incorporated into the Soviet Union. On June 14 and July 1, 1941, more than one thousand people from Saaremaa were deported to Siberia. In the middle of September German troops landed on the island of Muhu. By the beginning of October Saaremaa was occupied, remaining under German rule for three years. In 1944, before Soviet Army reached Saaremaa, many islanders fled Estonia and took refuge in Western countries, mainly in Sweden. 2000-3000 residents of Sõrve peninsula were deported to Germany; less than half of them could returned years later.
During the postwar period the fate of Saaremaa was strongly influenced by the fact that the island lay on the western border of a huge totalitarian state - the U.S.S.R. Saaremaa was restricted zone and therefore strict limitations were put on navigation and liberty to move on the island even for the ordinary Estonians, not to speak of foreigners. There were over 30 Soviet Army bases in the country. They had more than 4000 hectares of land (on the peninsula of Sõrve, ca 1600 ha) on Saaremaa.
In 1947 a foundation of collective farms was forced on the islanders. It was followed by another deportation to Siberia in March 1949 and mass movement from countryside both to Kuressaare and the mainland. The repressions committed by Stalin in 1941 and after World War II, and Hitler in 1941-1944, as well as mass emigration in 1944 reduced the county's population figure nearly by one third: it decreased to 40,000 by the end of the war. There was an extremely sharp decrease in the number of young people and therefore it was only in the early 1980s, when the county's population stopped declining. But this process was continuing on the little islands belonging to the county (Ruhnu, Abruka, Vilsandi).
Most remarkable is the destiny of the island of Ruhnu whose population consisted of ethnic Swedes. They all emigrated during the last war to Sweden and the population now is completely new, consisting of newcomers from the mainland and other islands.
In addition to the essential losses in population, Saaremaa as well as other Estonian islands could not determine on its own development, because everything was centralized and all decisions were made in Tallinn and Moscow. Little villages, schools, dairies, fishing cooperatives were abolished and big ones established instead.
On November 16, 1988, the Declaration of the Sovereignty of Estonian SSR was passed, which marked the beginning of peaceful struggle to regain the country's independence. On August 20, 1991, the Supreme Council of the Republic of Estonia declared the state an independent Republic. In June 1992 two important events took place in Estonia, the local currency - kroon - was implemented on June 20 and the referendum approved a New Constitution on June 28.
On September 20, 1992 the new parliament - Riigikogu - was elected.