St. Andrew, the elder brother of St. Peter, and like him, a fisherman of the lake of Galilee, on hearing St. John the Baptist proclaim that Jesus was the Lamb of God, was moved to follow Our Lord, who chose him to be one of the twelve apostles. It is believed that after the Resurrection, St. Andrew labored in spreading the Gospel in Eastern Europe, and made many converts.
At the last he was crucified in Patras in the Greek manner. In 357 his remains, together with those of St. Luke, were solemnly translated to the Church of the Apostles in Constantinople. His head is venerated at St. Peter”s in Rome. In 1210 his body had been moved to the Cathedral at Amalfi in the Kingdom of Naples. His feast is important not only on account of the position it holds in the Missal (at the beginning of the Proper of the Saints) but more especially on account of the antiphons of the Divine Office and the passages from Holy Scripture read at the Mass.
(Source: Fr. Lasance, The New Roman Missal)