Many heroic men and women died during World War II, refusing to renounce their Christian faith even under the threat of death.
There were so many in Poland in particular that it would be difficult to celebrate each martyr on their own day during the liturgical year.
St. John Paul II beatified a large group (108 total) of these Polish martyrs on June 13, 1999, whom the church in Poland honors each year on June 12.
During the beatification Mass, St. John Paul II praised the virtues of the Polish martyrs and explained how their example can continue to inspire us:
If we rejoice today for the beatification of one hundred and eight martyrs, clergy and lay people, we do so above all because they bear witness to the victory of Christ, the gift which restores hope. As we carry out this solemn act, there is in a way rekindled in us the certainty that, independently of the circumstances, we can achieve complete victory in all things through the One who has loved us (cf. Rom 8:37). The blessed martyrs cry to our hearts: Believe in God who is love! Believe in him in good times and bad! Awaken hope! May it produce in you the fruit of fidelity to God in every trial!
Roman Martyrology
The Roman Martyrology, which is a listing of every saint commemorated by the Catholic Church, brings to mind many of these martyrs on the days of their deaths.
Many of them died in the month of October. Here is a selection of each martyr and what the Roman Martyrology mentions about them.
October 2
At the city of Stanislawów in Poland, Blessed Maria Antonina Kratochwil, virgin of the Congregation of the School Sisters of Our Lady and martyr, who, during the war, was imprisoned for her faith, where she died under torture for Christ the Spouse.
October 5
At the town of Plonkowo in Poland, Blessed Marian Skrzypczak, priest and martyr, who, during the occupation of Poland by a regime hostile to God, was shot in front of the church and obtained the palm of martyrdom for his invincible faith.
October 10
At the town of Dzialdowo also in Poland, Blessed Leone Wetmański, auxiliary bishop of Płock, who, during the impious persecution perpetrated in Poland against men and against God, fulfiled his martyrdom in a prison camp with a fearless death.
October 12
In the extermination camp of Auschwitz near Krakow in Poland, Blessed Roman Sitko, priest and martyr, who, during the occupation of Poland in the course of the war, cruelly tortured by persecutors of human dignity and faith, passed to the vision of eternal bliss.
October 14
In the prison camp of Dachau near Munich in Germany, Blesseds Stanisław Mysakowski and Franciszek Rosłaniec, priests and martyrs, who, during the wartime occupation of Poland by enemies of God and human dignity, suffered the martyrdom in a gas chamber.
October 16
Near Krakow in Poland, in the extermination camp of Auschwitz, Blesseds Anicet Kopliński, of the Order of the Friars Minor Capuchin, and Józef Jankowski, of the Society of the Catholic Apostolate, priests and martyrs, who, during the military occupation of the homeland by the followers of an impious doctrine hostile to men and to the faith, testified to their faith in Christ until their death, one killed in a gas chamber, the other by camp guards.
October 31
At the town of Piotrków Kujawski in Poland, Blessed Leon Nowakowski, priest and martyr, who was shot during the military occupation of Poland for having strenuously defended the faith before the enemy regime of God.