Missing papers mar solidarity's celebrations

June 1979: Pope John Paul II visits Poland, to acclamation by huge crowds.

July 1980: Increases in food prices trigger a wave of strikes throughout Poland, culminating in August in the strike at the Gdansk shipyard.

August 1980: Gdansk Accords signed by Lech Walesa.

September 1980: The new, independent trade unions springing up all over Poland combine to form Solidarity.

December 1981: General Wojciech Jaruzelski imposes martial law and declares Solidarity illegal.

January 1989: Jaruzelski forced to include Solidarity and the Independent Students organisation among the participants at a round table to solve economic and social problems.

June 1989: Semi-democratic parliamentary elections in Poland. Solidarity-backed candidates take all seats they are permitted to fight.

August 1989: Communists lose their majority in parliament, opening the way to a Solidarity-led government.