St. Sebastian was an early Roman martyr. In 283, Sebastian joined the Roman Army. Instead of persecuting Christians, as was common practice during the time of Emperor Diocletian, Sebastian worked to assist Christian martyrs and converted many around him. He was eventually discovered and was sentenced to death by Diocletian.
It was ordered that Sebastian should be tied to a stake and shot full of arrows. When his body was as “full of arrows as an urchin,” he was left for dead. Sebastian was not dead, however, and recovered with the help of other Christians. Still, Sebastian did not hide or flee to save his life. Instead, he went to Diocletian and denounced his persecution of Christians. Sebastian was once more sentenced to death, this time by being beaten with clubs, which was successful in ending his life.
St. Sebastian’s patronage of athletes is likely due to his strength and success in the Roman Army.