The Democratic Union Party (Romanian: Partidul Democrat al Unirei or Partidul Democrat al Unirii, PDU) was a political group in Romania, one of the political forces which claimed to represent the ethnic Romanian community of Bukovina province. The PDU was active in the wake of World War I, between 1919 and 1923, having for its leader the historian and nationalist militant Ion Nistor. It was formed by Nistor and other activists who wrote for the regional periodical Glasul Bucovinei, and, as a consequence, the party members were commonly referred to as Glasiști ("Glas-ists").