Workers at the Lenin Shipyard in Gdansk
(Danzig), Poland, went on strike when one of their own, a crane
operator named
Anna Walentinowicz, a labor agitator, was fired by the
authorities (link is to the BBC story at that time, and there
is a contemporary video clip of another news story at the
site).

The Polish words in white are 'It all began in Gdansk'
An overview of the events in Poland is at
Poland 1980-81,
We've caught God by the arm.
The English site of the Independent and Self-Governing Trade Union
Solidarity (NSZZ "Solidarnosc")
is here.
Commemorations are taking place in Poland and elsewhere of these
events, including the August 31, 1980, agreement between the
Government and the Inter-enterprise Strike Committee, and there is
a listing here.