Saint Peter
Peter (d. ca. 64), leader of the Apostles, first Bishop of Rome (Pope). According to the Gospel, a fisherman known as Simon was called to follow Jesus, who gave him the name Peter and declared him "The rock upon which I will found my Church." Though Peter was his closest disciple, Christ prophesized his betrayal. Following the Resurrection, Peter preached extensively and became the first leader of the Church in Rome. He was martyred by Emperor Nero, reportedly asking to be crucified upside-down, for he was not worthy to die in the manner of his Savior.
Excerpt from The Golden Legend
[St. Peter] was taken of the ministers of Nero and was delivered to the provost Agrippa, then was his face as clear as the sun, as it is said. Then Agrippa said to him, "[You are] he [who glorified] in the people, and in women, [whom you inspire to depart] from the bed of their husbands." [The apostle denied this], and said to him that he glorified in the cross of our Lord Jesus Christ. Then Peter was [sentenced] to be crucified as a stranger, and because that Paul was a citizen of Rome it was commanded that his head should be [cut] off.
... And when the horrible time came of their end that they were departed that one from that other, they bound the pillars of the world, but that was not without wailing and weeping of the brethren. ... [So said] St. Dionysius, and as Leo the Pope and Marcel witness, when Peter came to the cross, he said, "When my Lord descended from Heaven to the Earth he was put on the cross right up, but me whom it [pleases] him to call from the Earth to Heaven, my cross shall show my head to the Earth and address my feet to Heaven, for I am not worthy to be put on the cross like as my Lord was, therefore turn my cross and crucify me my head downward." Then they turned the cross, and fastened his feet upward and the head downward. Then the people were angry against Nero and the provost, and would have slain them because they made St. Peter so to die; but he required them that they should not let his passion, and as Leo [witnessed], our Lord opened the eyes of them that were there, and wept so that they saw the angels with crowns of roses and of lilies standing by Peter [who] was on the cross with the angels.