The Town of Luna was formerly called Namacpacan. “Namacpacan” is an ilocano word which means “one who had given food.”Based on early records, Namacpacan was a visita (a settlement with a church but is visited by non-resident clergies whose headquarters are at the cabecera) of Purao, now Balaoan, as early as 1587.  It was a settlement along the camino real (national road) from Vigan to Manila and travelers stopped and refresh themselves at that place.  The era of restaurants was not yet introduced during that time, and so the families of that town offered the travelers food and shelter, hence, the name of the place.The settlement grew and on November 25, 1690, Namacpacan was founded as a town ans parish with St. Catherine of Alexandria, virgin and martyr, as patroness.  Since then, the town and patronal fiesta have always been celebrated every November 25.  The original site of the town was in Darigayos, as settlement with a small cove which served as a harbor for sea-going vessels.  In 1741, the parish was transferred to the place where it is now.The town of Luna has become a by-word especially among catholic devotees because of the several miracles that are attributed to our Lady of Namacpacan.  Our lady of Namacpacan is a beautiful image of the Blessed Virgin Mary.  It was in 1871 when a galleon that came all the eay from Mexico to deliver a statue of the Blessed Virgin to the Immaculate Concepcion Seminary in Vigan, Ilocos sur, stopped by Darigayos to sek cover from the stormy weather.  According to traditional accounts, when the storm, is over, the galleon could not proceed to its destination because the sea became rough and unnavigable whenever the crew launched the vessel.  They decided to bring the statue to Vigan by land.  While making preparations, the statue was brought to the convent.  The church at that time was undergoing repairs on the damaged portions brought about by a strong earthquake.The following morning when the trip to Vigan was commence, the men could not move the statue from the place where it stood.  Fray Camilo Naves, an Augustinian priest, interpreted this as a message that the Blessed Virgin wanted her statue to remain in the parish.  Negotiations were made with Church authorities who ordered the statue from Spain.  It was agreed that the Catholics from Namacpacan would reimburse all expenses incurred and the parishioners contributed joyously and generously to the extent of selling portions of their fields to raise the amounts.  An altar at the northern portio  side of the church was constructed to house the statue of the Blessed Virgin Mary, Our Lady of Namacpacan.On October 18, 1906, during the incumbency of Governor Joaquin Luna and Namacpacan Mayor Primitivo Resurreccion Novicio, the name of the town was changed to Namacpacan to Luna by virtue of Philippine Commission Act No. 1543.  It was the first town that altered its name since the creation of the province in 1850.  The change was based on the request of the municipal council which was subsequently approved and endorsed by the Provincial Board of La Union, in honor of the famous Luna brothers: Antonio, the General and Juan, the Painter, whose mother Doña Laureana Novicio Luna, was a native of the locality.