In 1492 Christopher Columbus discovered the new world and claimed it for the glory of the Spanish Crown.  Within fifty years Spain's domain had spread to include South America, Central America, present day Mexico and into North America.   A wave of conquistadors overpowered the native peoples and their lands.  As the conquest spread, however, the Spanish Crown realized that they would not have the citizenry to settle the new colonies.  A new goal developed.  Now the aim was to make converts and tax paying citizens of the indigenous peoples they conquered.

The Spanish mission system arose in part from the need to control the colonies.  Realizing that the colonies would require a literate population base that the mother country could not supply, they initiated a system of missions with the goal of converting the indigenous people to Christianity.  Jesuit priests were sent into the expanding empire with their priority of converting souls to Christianity.  The mission system served an entirely different purpose for the natives.  They were enticed by the food, clothing and supplies that the priests offered, but they also saw the missions as a chance to gain some education.

The Spanish mission system was organized around missionary sectors.  Each sector could have several rectorates which were, in turn, responsible for a cluster of missions. Nuestra Senora de los Dolores became the rectorate for the Kino missions and Padre Kappus was the first Superior.  Each mission would consist of a cabecera or resident headquarters and visitas or outlying mission stations.

During Father Eusebio Kino's stay in the Pimeria Alta he founded twenty-some missions in eight mission districts.  The missions founded by Kino include:

• Nuestra Señora de los Dolores - March 13, 1687
• Nuestra Señora de los Remedios - 1687
• San Ignacio de Caburica - 1687
• San Pedro y San Pablo del Tubutama - 1687
• Santa Theresa de Atil - 1687
• Santa Maria Magdalena - 1687
• San Jose de Imuris - 1687
• Nuestra Señora del Pilar y Santiago de Cocóspera - 1689
• San Antonio Paduano del Oquitoa -1689
• San Diego del Pitiquito - 1689
• San Luis Bacoancos - 1691
• San Cayetano de Tumacácori - 1691
• Los Santos Angeles de Guevavi - 1691
• San Lazaro - 1691
• San Xavier del Bac - 1692
• San Cosme y Damian de Tucson - 1692
• La Purísima Concepción de Nuestra Señora de Caborca - 1693
• Santa Maria Suamca - 1693
• San Valentine de Busanic - 1693
• Nuestra Señora de Loreto y San Marcelo de Sonoyta - 1693
• Nuestra Señora de la Ascencion de Opodepe (1704)
• Los Santos Reyes de Sonoita - (1692)

San Marcelo de Sonoyta was established at the O'odham village of Sonoídag or Sonoyta.  Today this area is immediately adjacent to the southeastern corner of Organ Pipe Cactus National Monument.  Father Kino visited her in 1698, 1699, twice in 1701, 1702 and 1706.  He described it as a flat level land good for planting and with irrigation canals.  On November 22, 1751 the O'odham Indians attacked the mission and made a martyr of Father Enrique Ruhen.  The Indians tore down the church and the priest's dwelling.  Juan Bautista de Anza, Fathers Font and Eixarch passed the ruins on 1 June 1796.

The churches at these missions were constructed by Indian craftsmen under the direction of the resident or visiting priest.  The were usually rectangular, hall-shaped simple adobe churches, but many had beautiful altars, paintings and other adornments.  They were built from materials at hand.  The adobe bricks utilized straw, twigs and stone particles while the burned brick used local clay.  The wood from the mesquite and pine trees were used for roof beams, lintels, doors, furniture, shutters and grills on the windows.  Saguaro cactus ribs and canes from ocotillo were used for roofs as well.  The walls were covered with thin, hard adobe mud plaster and heavy coats of whitewash.

Very little remains today of the churches that Father Kino built.  There are a few adobes inside the walls of Cocóspera and under the mounded ruins of Remedios.  The churches that are seen at the missions today are the work of the Franciscans or modern day builders.

"By the first half of the eighteenth century, a few of the older Jesuit missions in Northern Sonora began to reflect a stability achieved through almost a half century of proselytizing among the resident Lower Pimas, Opatas, and Jovas and through the inexorable colonization of the area by Spanairds.  A handful of more permanent churches replaced the earlier adobe buildings." (The Pimeria Alta, The Southwestern Mission Research Society)  Among these churches were San Miguel Arcángel de Oposura and Cucurpe.  Contemporary with these churches was Nuestra Señora de la Asunción at Arizpe.