Gaude mater Polonia

Gaude Mater Polonia (Latin, "Rejoice, oh Mother Poland") was probably the most popular medieval Polish anthem, written in the 13th or the 14th century in memory of Saint Stanisław Szczepanowski, Bishop of Kraków. Polish knights used to sing it after victory in battle, presumably to one of the Gregorian melodies associated with the Eucharistic hymn O Salutaris Hostia on which it is based.

The anthem came to existence in 1253, along with the canonisation of Stanisław Szczepanowski on 8 September in Assisi; Stanisław died a martyr's death on 11 April 1079. The author of the anthem is the first Polish composer in music history known by name, the poet Vincent of Kielcz, OP, a Cracovian canon and chaplain of Bishop Iwo Odrowąż. For a long time he was mistakenly called Vincent of Kielce, and he wrote the hymn to commemorate the canonisation of St Stanisław. It is assumed that the first performance of the piece took place on 8 May 1254, during the canonisation ceremonies in Kraków.

Vincent wrote The History of St. Stanislas in Latin (Dies adest celebris). The poet decided to describe the life and accomplishments of Bishop Stanisław and the miracles which occurred after his death, which people had been speaking of for almost two centuries. The legend says that after the body of St. Stanisław was cut into pieces, the parts miraculously regrouped and formed the whole body again, while eagles circled in the sky. This was an allegory of the current state of Poland in those years: split into pieces but hoping to grow back together to form a country again. The uniting of Poland occurred a couple years after the canonization of St. Stanisław under the rule of King Władysław I the Elbow-high.

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