High Quality Content by WIKIPEDIA articles! The Social Democratic Party (Hungary) often known as the "Historical" Social Democratic Party ("történelmi" Szociáldemokrata Párt, SZDP) is a Hungarian political party that emerged following a split within the Hungarian Social Democratic Party (MSZDP) in 1989. Both the SZDP and MSZDP lay claim to the same heritage: the Social Democratic Party which was part of a governing coalition in Hungary between 1945 and 1948, and a short period in 1956, which itself was renamed from the Hungarian Social Democratic Party, previously established in 1890. Traditional areas of support have been the industrial areas of Budapest, especially Obuda, Pesterzsébet and Angyalföld.