In 1980, life in Poland was getting expensive. The price of food was rising fast, and wages weren't keeping up. Workers began to strike in protest.
The Baltic city of Gdansk had grown into something of a hotbed of resistance to the Communist government. And it was the workers in the Lenin Shipyards who were the most rebellious.
The firing of crane operator and activist Anna Walentynowicz was the last straw. And on 14 August, 17,000 workers went on strike and took control of the shipyard. They were led by the impressively mustachioed electrician Lech Walesa.
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The Gdansk strike inspired others throughout Poland, and soon workers in 200 factories across the country had downed tools. They handed a list of 21 demands to the government, including the right to strike and the right to form independent trade unions.
The government caved in, and on 31 August, agreed the Gdansk Accords, conceding many of the workers' demands.
And so, on 17 September, a group of workers' representatives formed Solidarity, the first independent trade union the Soviet bloc had ever seen, and Lech Walesa was elected president.
Over the next 18 months or so, membership grew to nearly ten million. It soon became a social and political force, demanding economic reform and greater freedom.
General Wojciech Jaruzelski, under pressure from the Soviet Union, imposed martial law in 1981, and in 1982 declared Solidarity illegal. It spent the next few years as an underground organisation.
But support flooded in from overseas. Confusingly for many, world-class union-basher Margaret Thatcher became a fan, along with top lefty Tony Benn, plus Ronald Reagan, and the Pope.
In 1988, a fresh wave of strikes and protests broke out. And in 1989, the government agreed to legalise Solidarity, and to allow it to participate in free elections. Solidarity swept the board, winning 99 of 100 seats in the Senate, and all the seats it was allowed to contest (162 out of 460) in the lower chamber.
Solidarity formed a coalition government, and Tadeusz Mazowiecki, the party's leader, became eastern Europe's first non-communist prime minister for nearly 40 years.
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