The Social Democratic Party has been one of the, if not the most, constant party in Estonian politics. The origins of the Social Democratic movement can be traced to the revolutionary year of 1905. A little more than a decade later, in 1919, social democrats won 3/4ths of the seats in the Estonian Constituent Assembly. It should be noted that Estonian Social Democrats belonged to the Socialist International (SI), the worldwide organisation of social democratic, socialist and labour parties, and their membership status was renewed after Estonia regained its independece.

Estonian Socialist Party Foreign Representation was the main reason why our party continued to exist. They joined three other parties in September of 1990 and formed Estonian Social Democratic Party, led by Chairwoman Marju Lauristin. After the restoration of independence, parliamentary elections followed. Social Democrats campaigned under a coalition party called the Moderates (Mõõdukad) and were succesful in winning twelve seats in the parliament, four of which went to social democrats in the right-centre government formed by prime minister Mart Laar. Those four were Secretary of Social Affairs Marju Lauristin, Secretary of Environment Andres Tarand, Secretary of Federal Reforms Liia Hänni and Secretary of Agriculture Jaan Leetsaar.

In the fall of 1994 Parliament passed a vote of non-confidence in Mart Laar’s government; the head of the Moderates, Andres Tarand, became the prime minister in charge of the new government. There were three members from the Moderates in the new government: Secretary of Regional Affairs Eiki Nestor, Secretary of Federal Reforms Liia Hänni and Secretary of Agriculture Aldo Tamm.

The Moderates didn’t fare so well during the election in the following year; they only won six seats in the Parliament. An electoral alliance was formed with Estonian Rural Centre Party (Eesti Maa-Keskerakond) in 1996 and the coalition’s name remained the Moderates.

Three years later the Moderates in coalition with Pro Patria Union (Isamaaliit) and Reform Party (Reformierakond) won the elections and were called the Triple Alliance. The Moderates had seventeen seats in the Parliament and five seats in the government. After a period of working together, the Moderates were joined by Estonian People’s Party, led by Toomas Hendrik Ilves, which was created by combining two small parties Peasants’ Party (Eesti Talurahva Erakond) and People’s Party of Republicans and Conservatives (Vabariiklaste ja Konservatiivide Rahvaerakond). The unification was formally approved by party general assembly in the fall of 1999.

In the second Mart Laar government, the Moderates carried five seats: Secretary of Agriculture Ivar Padar, Secretary of Foreign Affairs Toomas Hendrik Ilves, Secretary of Population Affairs Katrin Saks, Secretary of Social Affairs Eiki Nestor and Secretary of Finance Mihkel Pärnoja (later replaced by Henrik Hololei).

Toomas Hendrik Ilves was elected as a chairman of the Moderates party during the 2001 general assembly. Additionally, the party approved the new so-called Third Way program, which confirmed the party’s social democratic world view.

The Triple Alliance government collapsed in January of 2002 and the Moderates became the opposition party in Parliament.  The party’s image had suffered especially due to controversial land privatization decisions and in October 2002 Ilves stepped back as a chairman after the loss in the local elections in Tallinn. Ivar Padar became the new chairman of the Moderates. During the 2003 Parliament elections the party won six seats. During that time, the party went through a deep reorganization phase and renamed themselves Social Democratic Party (SDE) on February 7, 2004. A few months later during the European Parliament elections SDE astonishingly won three seats out of six and regained the support of 37% of the electorate. Toomas Hendrik Ilves on his own won more votes than several other parties combined. It came as no surprise that during the presidential elections in September 23, 2006 Ilves, a former chairman of the party, became President of Estonia.

The Social Democrats remained succesful during the parliamentary elections in March 2007; they won 10 seats and were included in the coalition after having been a minority party for a couple of years. Party chairman Ivar Padar became the Secretary of Finance in the new coalition government formed with Reform Party, Union of Pro Patria and the Social Democratic Party which was led by prime minister Andrus Ansip from the Reform Party. The chairman of Social Democratic Party Jüri Pihl became the Secretary of Interior Affairs and Urve Palo became the Secretary of Population Affairs. The new government soon had to face the April civil unrest where ethnic Russians rioted in response to the removal of a bonze statue that honors Soviet soldiers who defeated the Nazis. The Secretary of Interior Affairs Jüri Pihl’s forceful response to the riots is credited with limiting the spread of unrest.

During the general assembly meeting on March 7, 2009 Jüri Pihl was elected as a chairman of the Social Democratic Party. The coalition collapsed after fundamental disagreements about the bill regarding new labor contracts, Social Democrats became the opposition party in Parliament. During the June elections for European Parliament the party won one mandate which went to Ivari Padar.

By the fall of 2009 Social Democrats had gained more support during the local elections and took the lead in Tallinn after more than eight years. The party’s chairman Jüri Pihl became the new mayor of Tallinn.

A merger with People’s Union of Estonia (Eestimaa Rahvaliit or ERL) was discussed in 2010, but  at the party congress the merger failed to gain enough votes. Still, leading  ERL members left the party and joined the Social Democratic Party. Later that year Social Democrats promptly exited the coalition with the Centre Party after it was discovered that their chairman Edgar Savisaar accepted substantial funds from Russia.

During the general assembly on October 16, 2010 the party membership chose Sven Mikser, a longtime Parliament member, as the party’s chairman, who oversaw the election campaign for the upcoming Parliament elections in 2011. Social Democrats received their best results yet in these elections and won 19 seats in Estonia’s 12th Parliament.

After the 2013 municipal elections, the Social Democrats are represented in more municipalities than ever before. Social democrat mayors were appointed in Kuressaare, Paide, Põltsamaa, Valga and Võru. Over a long time the Social Democrats came to power in Tartu.

On March 20, 2014, the Social Democrats and the Estonian Reform Party formed a new coalition government which was led by prime minister Taavi Rõivas from the Reform Party. The chairman of Social Democratic party Sven Mikser became Minister of Defence, Urve Palo Minister of the Economic Affairs and Infrastructure, Ivari Padar Minister for Agriculture, Andres Anvelt Minister of Justice. Eiki Nestor was elected president of Parliament.

In the spring of 2014 at the European Parliament elections Social Democrats became one seat out of six. Social democrat Marju Lauristin became member of European Parliament.

In March 2015 at parliament elections Social Democrats won 15 seats in Estonia’s 13th Parliament. On April 8, 2015, the Social Democrats, Estonian Reform Party and Union of Pro Patria formed a new coalition government which is led by prime minister Taavi Rõivas from the Reform Party. The chairman of Social Democratic party Sven Mikser became Minister of Defence, Urve Palo Minister of Entrepreneurship, Indrek Saar Minister of Culture, Rannar Vassiljev Minister of Health and Labour. Eiki Nestor was elected president of Parliament.

On 30th May of 2015, at the party’s general assembly Jevgeni Ossinovski was elected as the chairman of the party. The same year in September the representatives of the Social Democratic Party changed in the Government. On 14th of September 2015 Jevgeni Ossinovski was appointed as Minister of Health and Labor, Liisa Oviir as Minister of Entrepreneurship, Hannes Hanso as Minister of Defence. Indrek Saar continued as Minister of Culture.