La Purísima was the eleventh of the California Mission Churches. Founded in the place, “Paraje de Alascupi” as named by the Indians on December 8, 1787, Feast of the Immaculate Conception. Most Reverend Frances Xavier Lasuen OFM, second President of the California Missions, blessed water and with it the place, and raised the cross. He celebrated Mass, preached for the first time, and appointed Fr. Vicente Fuster as Parish Pastor with Fr. Joseph Arroita his assistant. However, it was not until the following April that building began on the mission and the real beginning of Catholic life in this area. The first entry in the baptismal book is "On April 9, 1788 Indian Matzzaguit was baptized with the name of Francisco de Conception by Fr. Jose Arrorta.” In 1789, there were 151 neophytes, in 1799, the number had risen to 923 and in 1805, and it reached the astounding number of 1385. The first confirmation class on December 9, 1790 numbered 75 and Padre Lasuen administered the sacrament.

In 1802, the first adobe Church was built with Fr. Gregorio Fernández as Parish Pastor and dedicated on December 8 of that year. By 1810 Fr. Mariano Payaros, one of the most illustrious of the Parish Pastors had completed a large catechism with the acts of Faith, Hope, Charity, and Contrition all in the language of the natives. Then, on December 12, 1812 came the great earthquake, which destroyed the Church burying under its walls the imported images and paintings and making uninhabitable most of the mission buildings. It was not worth rebuilding on its original location so Fr. Payeros, then Parish Pastor, moved the mission 2 miles distant to the dale called Los Berros where it now stands.

In October of 1874, the country around the old Mission was divided into farms. The settlers established what is now the city of Lompoc as a temperance settlement of 200 families. The Catholic families were serviced from Mission Santa Ines. In 1875, Father McNally, Rector of Mission Santa Inés, went about gathering support to build a Roman Catholic Church in Lompoc. So successful were his efforts that Protestants and Catholics alike contributed liberally to the project. The Old Frame Church was soon built on the comer of Olive and I streets on property purchased from Nellie Hooker and services were held on 12 December 1875. Christened, "La Purísima” taking its name from Mission La Purísima Conception founded here in 1787. In the tower of the frame church, according to old news reports, was hung one of the original bells from the old Mission.

In December o f 1910, Fr. John Reynolds became the first resident of the new La Purísima and took over in January of the following year. He was succeeded by Fr. Raley who was instrumental in erecting the concrete illuminated cross that still stands a block from the site of the original mission. The rectory was built by Fr. Raley and enlarged by Fr. Woodcutter, his successor. Fr. Thomas Morris came in June 1918 and within two years; he had built the old La Purísima at a cost of $26,000.

On December 8, 1920 this Church was dedicated by Bishop Cantwell and Monsignor John Cawley, V. G. gave the address. For forty years, this church was to serve the Catholic people of Lompoc Valley until it became inadequate.

Rev. Andrew McGrath, born in Waterford, Ireland in 1913 and ordained in 1938, became Parish Pastor of La Purísima Church in Feb. 1955 to Dec. 31, 1986 when he retired as Msgr. Andrew McGrath. During his Parish Pastorate, the growth of the parish was truly astonishing, both population (baptisms averaged 184 per year) and facility-wise. In 1955, additional property was purchased and plans were made for a school and convent. On 8 Dec. 1956, two Sisters of Nazareth left Paris, France, for the long journey to Lompoc to aid in the establishment of the La Purísima School. The school was competed in May 1957, with six classrooms. Classes began on 10 September 1957 with 152 students.

Due to an increasing population and need for a social hall, Fr. McGrath purchased an old barracks building and put it to the rear of the rectory on the west side of I Street. This served as a parish hall until the current church could be built. It made for an easier transition of the old church into a parish hall. Plans for a new church and rectory were brought before the planning commission in March 1960. Fr. McGrath had a lively session with the planning commission about the excessive setbacks and parking spaces required for the church building project. He stated to the planning commission that we'd need to buy the airport for parking. Groundbreaking for the new church and rectory commenced in June 1960.

The new church and rectory was estimated to cost $250,000 and the church would seat 920. The new La Purísima Church was completed in May 1961, when the first Mass was celebrated. It was dedicated to our Blessed Lady under the title of Her Immaculate Conception (La Purísima) in December 1961 by His Eminence Cardinal McIntyre.

The church congregation settled in to enjoy the hard earned facilities. Fr. McGrath paused to plan for a new church annex at Mission Hills. With the building programs came the added responsibility of maintenance. By 1968, La Purísima Parish had 2,000 families, which was a 333% growth in thirteen years.