Christian Saints

        St. Dionysius the Aereopagite (Acts of the Apostles 17:34) was converted by St. Paul and became the first bishop of Athens. Then he moved to Gaul, where he became the first bishop of Paris. Arrested, he was subjected to many tortures (thrown to wild animals, to furnace, whipped, etc.), but he did not betray his faith. He then was beheaded on Montmartre ('Martyrs' Hill). The later legend fused Dionysius with St. Denis, who lived in France in the 3rd century. The monks of the Abbey of St. Denis near Paris encouraged this amalgamation. Under the persecutions of the emperor Valerian St. Denis was arrested, c. 250 AD.  According to the further legend St. Denis was beheaded together with his companions, the priest Rusticus and the deacon Eleutherius. All three after the execution rose, took their heads and walked all the way to the sepulchre. St. Denis continued to perform numerous posthumous miracles in the neighborhood of his tomb.
St. Denis is the patron saint of France.
See: Domenico and David Ghirlandaio and Bartolomeo di Giovanni. Madonna and Child Enthroned with Two Angels, St.
 Dionysius the Aereopagite and St. Dominic, Pope Clement and St. Thomas Aquinas.
 

Recommended reading:
The Great Collection of the Lives of the Saints, Vol. 2: October by Demetrius, Thomas Marretta. Chrysostom Pr, 1995.
Dionysius the Areopagite - The Divine Names and the Mystical Theology by C. E. Rolt. Kessinger Publishing Company, 1997.
Pseudo Dionysius: The Complete Works (Classics of Western Spirituality) by Colm Luibheid (Translator), Paul Rorem (Photographer), Pseudo-Dionysiu. Paulist Press, 1988.