[11][12] In January 2019, the party saw its founding members — Podemos, Anova, and EU, as well as the local tides — splitting and eventually coalescing around the Galicia en Común alliance.

[21][22] Negotiations throughout September 2015 ensued, but stalled over Podemos's demands of its name appearing on the ballot clashing with Galician-based parties' stance to set up an autonomous candidacy "without subordinations".

In an assembly held in Vigo on 30 July, Anova, EU and the local tide platforms voted in favour of constituting En Marea as a political party to contest the regional election.

[51][52] This had been opposed by the regional branch of Podemos, which had concurrently held a membership vote that resulted in 75% of party members favouring the electoral alliance format instead.

[56][57] A last minute deal was reached on 13 August, after national Podemos leader Pablo Iglesias anticipated that his party would run together with En Marea "whatever the formula was".

[72] In late 2018, a crisis concerning the election of a new party leadership resulted in a split between Luís Villares's supporters and En Marea's founding members, Podemos, Anova and EU.

[88] Ahead of the November 2019 general election, it considered an alliance with either CxG, Anova and the BNG or with Íñigo Errejón's Más País,[89] but talks were unsuccessful and it ultimately declined to run altogether.