The main bulk of my research in Poland concerns a British trade union called Solidarity. This is their logo.
And the reason I'm researching a British trade union while I'm in Gdańsk is because Solidarność (which means Solidarity in English) is a Polish trade union which has its origins in the city. This is their logo, which inspired Solidarity UK's logo.
Solidarność are famous here for their strikes in 1980 which allowed independent trade unions (i.e. not the state controlled, Communist union) to operate. Well, for a few months at least, before martial law was introduced in 1981.
Eventually, in 1989 when the political situation changed, concessions were made by the Communist ruling party and limited elections were held. With Solidarność backed candidates taking almost all of the available seats, the Communist party realised that they had no mandate to govern. The first presidential elections were held in 1990 and the leader of Solidarność, Lech Wałęsa became president.
Wałęsa wasn't a terribly successful President, he was a symbol of the turbulent struggle of the 80s where oppositional politics was simple and unified. The move to a free market was economically difficult for Poland and he lasted for one term. After he lost the 1995 elections, he went into "political retirement" and apart from an unsuccessful run in the 2000 Presidential elections (he scored 1% of the vote) his role in politics has been increasingly marginal.
He finally left Solidarność in 2006, because Solidarność had supported the right wing 'Law and Justice' party in the 2005 elections. Law and Justice were the Euro-sceptic (and homophobic...) party that the Conservatives cosied up to in the European parliament a few years ago.
As far as I can tell, it wasn't the social conservatism of Law and Justice to which Wałęsa objected, rather it was just another feud in the long history of splits and arguments within the union.
More recently he was accused of having worked with the secret police in the 1970s. His codename was Agent Bolek, which is also the name of a cartoon character from around that time.