The Pantheon of Illustrious Sailors () is a mausoleum and memorial to all the mariners of the Spanish Navy, especially prominent ones, and to the Spanish Navy and all its ships, battles and explorations in general. The term Pantheon is a concession to the generally prevalent and popular style of neoclassical architecture, which is supposed to have begun explicitly in the 18th century, but was in use long before then in the Renaissance, a "rebirth" of classical civilization, especially in decorative ornamentation.
The application of "Pantheon" in this case is entirely superficial. The building is composed of two layers: a Catholic church to which a cemetery has been added by enclosure and roofing. The church projects above the roof of the building, while the cemetery appears as projections off the nave. The philosophic term Pantheon comes from a different, polytheistic religion. Etymologically, it refers to a panoply of "all the gods." Christianity, however, is considered a monotheistic religion, despite the Trinitarian subdivision of divinity into three persons. As each person is fully God, and is not lessened by division, the Trinity is described as a mystery.
The application of the term to the building, however, is entirely architectural. The Spanish architects who assigned the term believed they were creating a type of building, which, in the 18th and 19th centuries, was termed a Pantheon, because of the central dome. The earliest extant instance of a large domed structure is the Pantheon of Rome. Originally a pagan temple, it utilized the principle of the arch to support a heaven-like surface over a public chamber, the rotunda. Geometrically a dome is an arch rotated about a central axis, so whatever load-bearing advantage an arch has is multiplied over the dome. The Roman Pantheon survived because it was quickly converted into a Christian church, like many other pagan public buildings. Domes became a standard feature of state and religious buildings thereafter. Their sudden labelling as Pantheons in the 18th century is no doubt a neoclassicism, and there are others, such as a few frontal columns. The architecture, however, is primarily church architecture, none of which dates to classical times.
Military community of San Carlos
The Spanish naval pantheon is located in Poblado Naval de San Carlos, historically the Población Militar de San Carlos, in the Province of Cádiz, Andalusia, Spain. The "population" part of the name can be any community in English. Here it means district, whether naval or military, which would be covered by the general English term, "base." The base is continuous with the city of San Fernando, on the north side of it, except for the security barriers delimiting the base. The post office, the telephone company, and the "population" consider the base as part of the city. However, it never was in any municipal sense. The Población was there first, and was named San Carlos. It was treated as a town. San Fernando grew to the south of it, on land not on the base. They were both on an island, a slight elevation in the wetlands, the Isla de León, on the Bay of Cádiz. The land and structures of the base were acquired by, and are administered by, the national government, today the Ministry of Defence. For example, in the military legal system, the base is the headquarters of Juzgado Togado Militar Territorial Nº 22, "Territorial Military Court District Number 22," comprising Cadiz, with an address of Poblado Naval de San Carlos San Fernando (Cádiz).
Like any base of any country, the units at the base, their function in the military, the facilities available, and the relationships to the civilian community, change frequently as the military is brought up to date. Whether the base is the Población Militar de San Carlos, or the Poblado Naval de San Carlos, or just plain San Carlos, and whether it is on land belonging to San Fernando, or the Defense Department, are ongoing controversies not likely to be settled soon. These changes all affected the architecture and accessibility of the Pantheon one way or another.