Lafontaine held the positions Minister-President of the state Saarland and Federal Minister of Finance.
Lafontaine chaired the social-democratic party SPD from 1992-1993 and was its candidate for chancellor.
In 2005 he left the SPD for the The Left which was formed from a merger of the Labour & Social Justice Party ( WASG ) and the PDS which was preceded by the State Party of the GDR, the SED>