Social Democratic Union may refer to:
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Social Democratic Union (Croatia)
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Social Democratic Union (Ireland), started by Tommy Broughan in 2014 after he left the Labour Party
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Social Democratic Union (Latvia)
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Social Democratic Union (Serbia)
The Social Democratic Union ( sr, Социјалдемократска унија, Socijaldemokratska unija; abbr. СДУ, SDU) was a minor social democratic and leftist political party in Serbia. In 2020 Party merged into Party of the Radical L ...
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Social Democratic Union (Romania)
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Social Democratic Union (Ukraine)
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Social Democratic Union of Macedonia
The Social Democratic Union of Macedonia ( mk, Социјалдемократски сојуз на Македонија – СДСМ, ''Socijaldemokratski Sojuz na Makedonija'' – SDSM, sq, Lidhja socialdemokrate e Maqedonisë – LSDM) is a ...
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Social Democratic Union of Workers and Smallholders
Social Democratic Union of Workers and Smallholders ( fi, Työväen ja Pienviljelijäin Sosialidemokraattinen Liitto, TPSL) was a political party in Finland. TPSL originated as a fraction of the Social Democratic Party of Finland, headed by Emil ...
, a political party in Finland
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Social Democratic Union 'Proletarian', a political party in Bulgaria
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Social Democratic Unionists
The Social Democratic Unionists ( - ''al-Wahdawiuyun al-Dimukatiyyun Al-Ijtima'iyyun'') is a political party in Syria. It was part of the National Progressive Front of legally licensed parties which support the socialist and Arab nationalist ori ...
, a political party in Syria
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Polish Social Democratic Union, defunct political party in Poland
{{disambig, political