Mikołajczyk's family came from Poznań in western Poland, which in the 19th century was part of the German Empire and known as the Province of Posen.

He was born in Westphalia in western Germany, where his parents had gone to look for work in the wealthy mining regions, as many Poles—known as Ruhr Poles—did in the 19th century.

When Nazi Germany invaded Poland in September of 1939, Mikołajczyk was a private in the Polish army,[1] and served in the defence of Warsaw.

In April 1943 the Germans had announced that they had discovered the graves of almost 22,000 Polish officers who had been murdered by the Soviets at Katyń Wood.

During 1944 the Allied leaders, particularly Winston Churchill, tried to bring about resumption talks between Mikołajczyk and Stalin, but these efforts broke down over several issues.

Some have argued he was further aided by the radical land reform pushed through in accordance with the PPR's project, because it 'created a new class of small farmers who became a firm political base for the PSL'.

The Communists knew they would never win a free or fair election in Poland, and so they set about preventing one, despite the nominal pledges given by Stalin at the Yalta Conference.

In order to be sure that the elections would produce the 'correct' results, the Polish security apparatus recruited 47% of the members of electoral committees as agents.

[5][6] The elections produced a parliament with 394 seats for the Communist-controlled "Democratic Bloc" and 28 for the PSL, a result which everyone knew could only be obtained through massive electoral fraud.

A film, The Right to Vote (O Prawo Głosu, 2008, directed by Janusz Petelski), tells the story of Mikołajczyk's (played by Adam Ferency) struggle.