Imperial Orb

The globus cruciger (Latin, "cross-bearing orb"), also known as the orb and cross, an orb (Latin globus) topped (Latin gerere, to wear) by a cross (Latin crux), has been a Christian symbol of authority since the Middle Ages, used on coins, in iconography, and with the sceptre as royal regalia. The cross represents Christ's dominion over the orb of the world, literally held in the hand of an earthly ruler (or sometimes it is held by an angel). In the iconography of Western art, when Christ himself holds the globe, he is called Salvator Mundi, the Saviour of the World; his statue is the Infant Jesus of Prague.

Holding the world in one's hand, or more ominously, under one's foot, has been used as a symbol since antiquity. To citizens of the Roman Empire, the plain round globe held by Jupiter represented the world, or the universe, as the dominion held by the emperor. A 2nd-century coin from the reign of Emperor Hadrian shows the Roman goddess Salus with her foot upon a globus, and a 4th-century coin from the reign of Emperor Constantine I shows her with a globus in hand. The orbis terrarum was central to the iconography of the Tetrarchy, representing the Tetrarchs' restoration of security to the Roman world. Constantine I claimed to have had a vision of a cross above the sun, with the words "In this sign, you shall conquer", at the Battle of Milvian Bridge in 312. His soldiers painted crosses upon their shields, and then defeated their foe, Maxentius.

With the growth of Christianity in the 5th century, the orb (in Latin scriptures orbis terrarum, the 'world of the lands', hence the word "orb") was topped with a cross (hence globus cruciger), symbolising the Christian God's dominion over the world. The emperor held the world in his hand, to show that he ruled it on God's behalf. To non-Christians already familiar with the pagan globe, the surmounting of a cross sent a message about the triumph of Christianity. In medieval iconography, an object's size, relative to that of nearby objects, indicated its relative importance; so the world was small and the one who held it was large, to emphasize the nature of their relationship. Although the globe symbolized the entire Earth, its use spread among many Christian rulers (some of them not even sovereign) who reigned over small parts of the earth.

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