Labour turmoil in 1980 led to the formation of the independent trade union "Solidarity" ("''Solidarność''"), which over time became a political force. Despite persecution and imposition of martial law in 1981, it eroded the dominance of the Polish United Workers' Party and by 1989 had triumphed in Poland's first partially free and democratic parliamentary elections since the end of the Second World War. Lech Wałęsa, a Solidarity candidate, eventually won the presidency in 1990. The Solidarity movement heralded the collapse of communist regimes and parties across Europe.