[9] Spring and the Democratic Left Alliance (SLD) initially cooperated in 2019 during the October 2019 parliamentary election, as part of The Left alliance.

[14] As a consequence, in 2020, SLD changed its name to the New Left as the new party was to be based on the structures of the alliance.

On 11 June 2021, the Spring's general assembly voted in favour of dissolving the party in order to merge with the SLD.

[16][17] It joined the four-party coalition that nominated Donald Tusk as its candidate for prime minister.

It received four seats in Tusk's cabinet, with Krzysztof Gawkowski as a deputy premier.