The Pantheon is a building in Rome. It was originally intended as a temple to all the gods and has been used since the 6th century as a Catholic church. Though the monumental inscription over the Corinthian columns on the porch claims a building date during the third consulship of Marcus Vipsanius Agrippa around 27 BC, the Pantheon was completely rebuilt in about A.D. 125, during the rule of Hadrian, as archeologists studying the date-stamps on the Roman bricks discovered.
Hadrian seems to have intended the Pantheon as a temple to all the gods (pan + theoi) that would represent the Roman Empire in its decorative materials as well as in an underlying idea. The plan of the building is circular with a rectangular block Corinthian portico opening into the rotunda.
The Panthéon is a building in Paris with a fascade resembling that of the Pantheon in Rome. It was built around 1757 by the architect Jacques-Germain Soufflot; its use repeatedly switched between church and secular building. Nowadays it houses the remains of important Frenchmen such as Voltaire and Jean-Jacques Rousseau.
A pantheon has also come to mean a set of gods from a common religion or mythology. A pantheon generally consist of all gods present in the given religion, although some pantheons mingle in unexpected ways, such as the roman and greek.