It was formed in 2007 as the legal successor to ['solid] – die sozialistische jugend (en: Solid: the socialist youth) which was the unofficial youth wing of the Left Party and its predecessor PDS.

The name "solid" comes from sozialistisch, links, demokratisch (socialist, left, democratic.)

Solid: the socialist youth was formed in Hanover in June 1999 and was accepted by the Party of Democratic Socialism as a youth organisation "close to PDS" in March 2002.

Before 1999 the PDS's youth organisation was Arbeitsgemeinschaft Junge GenossInnen; since then, most young members of the Left-Party have concentrated within ['solid].

But due to differences, other young members formed the "PDS Youth", a youth organisation integrated within the party and by self-definition of the group serving to form future cadres for the full-fledged party.