The original San Sebastian Church was a humble affair: wood walls under a galvanized iron roof, built in 1825 by Fr. Julian Gonzaga, a young priest from Barcelona who served the parish from 1818 to 1836. Gonzaga had arrived in Bacolod during its formative years as a town, just over a decade after Fr. Leon Pedro had been appointed the first parish priest in 1806. The church started with a medium-sized bell, but parishioners and clergy gradually expanded its voice. Fr. Roman Manuel Locsin donated a large bell, and Fr. Mariano de Avila added another when he became parish priest in 1863 after Locsin's death. These bells would become characters in their own right, their fate intertwined with the cathedral's physical story for the next century and a half.

The wooden church gave way to stone on April 27, 1876, when Fr. Mauricio Ferrero of the Order of Augustinian Recollects began construction of the structure that stands today. The materials came from across the archipelago: coral stone quarried on the island of Guimaras, hardwood from the forests of Palawan. The labor came from an unexpected source. The politico-military governor, Roman Pastor, provided prison labor for the project and persuaded Fr. Ferrero to design and supervise a stone prison as well -- the old Provincial Jail. Fr. de Avila's bell was installed in the new bell tower during construction, linking the old wooden church to the rising stone one through the continuity of its voice. Fr. Ferrero also built the parish rectory, now the bishop's house, starting construction on May 21, 1891, and finishing in 1894, using the same Guimaras coral and Palawan hardwood, with locally made bricks laid by Chinese masons.

In 1956, Bishop Manuel Yap consecrated the renovated cathedral in ceremonies presided over by the Apostolic Nuncio. The main altar was simplified, and a life-size statue of Saint Sebastian was enshrined. Further renovation came under Antonio Fortich, who became the third Bishop of the Diocese of Bacolod in 1967. Then, in 1969, the Bacolod City Engineer's office declared the bell towers a public hazard. Fr. de Avila's bell was removed from the belfry, and the towers were demolished. The church organ was disassembled and never reassembled. The cathedral's rector, Fr. Antonio Santes, raised funds to rebuild the towers in their present form, but the original bells needed a new home. In 1976, the Lions Club of Bacolod built a special belfry where Fr. de Avila's bell and Fr. Ferrero's smaller bell hang today -- survivors of wooden churches, stone reconstructions, and demolition orders, still sounding over the city.

Saint Sebastian, an early Christian martyr, was the protector chosen by Spanish missionaries for the coastal village that would become Bacolod. The association dates to the mid-1700s, before the village even bore the name Bacolod. When corregidor Luis Fernando de Luna donated a relic of the saint between 1777 and 1779, the village's identity became fixed: San Sebastian de Magsungay. Today, the cathedral serves as the seat of the Diocese of Bacolod and remains the city's most prominent religious landmark. On December 25, 1994, Bishop Camilo Gregorio declared the nearby San Diego Parish Church a pro-cathedral, extending the cathedral's spiritual reach. The remains of the diocese's first two bishops, Casimiro Lladoc and Manuel Yap, rest in the cathedral's columbarium alongside church benefactors, tying the building to the institutional memory of the diocese itself. The hill that refugees from pirate raids once climbed for safety now anchors a city of over 600,000 people, and the saint they brought with them still watches over it.