In April 2010, Tatyana Doncheva, a former Bulgarian Socialist Party (BSP) deputy and member of the party's National Council, presented her new Movement 21 (D21) project, which she plans to set up as a civic association to be established as a non-governmental organization, and within a few months later became a political party.[2] In 2011, it was established as a political party.[3] D21 joined the BSP – United Left (BSP–OL) electoral coalition in the run-up to the October 2024 Bulgarian parliamentary election but left the alliance in 2025 following the BSP leadership negotiating to join government with GERB.[4]
In the 2015 Bulgarian local elections, the party won 25 municipal councilors in various municipalities, including among others Blagoevgrad, Garmen, Petrich, Lom, Sopot, Vidin, Tvarditsa, and Sofia.[8]
