Theodosius voluntarily handed Leo the throne.
Leo’s greatest achievement was to thwart the Arab
siege of Constantinople in 717–718. Although the Arabs
continued to be a threat, they never again endangered the
existence of the empire. Also important was his promul-
gation of the Ecloga, the fi rst Byzantine legal collection
since the Corpus iuris civilis of Justinian I.
Leo’s espousal of Iconoclasm, which condemned
religious art, in 726 caused a revolt in those portions
of Italy still under imperial control (Sicily had already
shown signs of resistance early in Leo’s reign). Tax
increases imposed by Leo may also have been a factor
in this revolt. Pope Gregory II—who lacked suffi cient
resources to withstand the Lombards and thus was still
dependent on the Byzantines’ military power—urged
the Italians to exercise moderation, even though Leo
(probably at about this time) removed parts of Illyricum
from papal jurisdiction. Pope Gregory III, who was less
conciliatory, also continued a limited cooperation with
the empire; but by this time the popes were allies of the
empire rather than its subjects. Leo may have caused
some immigration to Italy from the empire’s heartland,
though this mainly occurred during the reign of his
son. Refugees, many of them monks, augmented the
existing Italo-Greek population—especially monastic
communities—in Rome and central and southern Italy.
Iconoclasm seems to have been little enforced in Byz-
antine Italy.
Further Reading
Editions and Translations
Gouilland, Jean. “Aux origines de l’iconoclasme: Le témoinage
de Grègoire II.” Travaux et Mémoires, 3, 1968, pp. 243–367.
(Greek text and French translation of two letters of Pope
Gtegory II to Leo III protesting Leo’s Iconoclastic policies.)
Le liber pontifi calis, ed. Louis Duchesne. Bibliothèque des
Écoles Françaises d’Athènes et de Rome. Paris, 1955. (Not
a new edition, but incorporates the editor’s corrections, dele-
tions, and emendations up to his death and thus supersedes
earlier printings. The life of Gregory II in Liber pontifi calis
is the most important source for the effects of Leo III’s poli-
cies in Italy. As of the present writing there was no English
translation of Gregory II’s biography or of any other from the
Iconoclastic period.)
Nicephorus, Saint, Patriarch of Constantinople. Breviarium
historicum (Short History), trans., with commentary, Cyril
Mango. Dumbarton Oaks Texts, 10; Corpus Fontium His-
toriae Byzantinae, 13. Washington, D.C.: Dumbarton Oaks,
- (Short chronicle covering some of the same rime as
Theophanes. Nicephorus was an Iconophile patriarch of
Constantinople, dismissed by Emperor Leo V.)
Santoro, Anthony, trans. Theophanes’ Chronographia: A Chroni-
cle of Eighth-Century Byzantium. Gorham, Me.: Heathersfi eld, - (With maps; translates only the notices from 717 to 803,
but these years included most of the Iconoclastic epoch.)
Theophanes. Chronographia, ed. Charles de Boor. Leipzig:
Teubner, 1883–1885. (Reprint, 1963. Principal Greek source
for Leo’s reign, but badly informed and often confused on
Italian affairs.)
———. Chronographia: The Chronicle of Theophanes Confes-
sor—Byzantine and Near Eastern History, A.D. 284–813,
trans., with introduction and commentary, Cyril Mango and
Roger Scott, with Geoffrey Greatrex. Oxford and New York:
Oxford University Press, 1997.
Turtledove, Harry, trans. The Chronicle of Theophanes: An Eng-
lish Translation of Annus Mundi 6095–6305 (a.d. 602–813),
with Introduction and Notes. Philadelphia: University of
Pennsylvania Press, 1982.
Critical Studies
Anastos, Milton V. “The Transfer of Illyricum, Calabria, and Sic-
ily to the Jurisdiction of the Patriarchate of Constantinople in
732–733.” In Silloge Bizantina in Onore di Silvio Giuseppe
Mercati. Rome, 1957, pp. 14–31.
———. “Leo III’s Edict against the Images in the Year 726–727
and Italo-Byzantine Relations between 726 and 730.” Byzan-
tinischen Forschungen, 3, 1968, pp. 281–327.
Barnard, Leslie W. The Graeco-Roman and Oriental Background
of the Iconoclastic Controversy. Byzantina Neerlandica, 5.
Leiden: Brill, 1974.
Gero, Stephen. Byzantine Iconoclasm during the Reign of Leo
III, with Particular Attention to the Oriental Sources. Corpus
Scriptorum Christianorum Orientorum, 384, Subsidia, 52.
Louvain: Corpussco, 1977. (Source for Leo’s early years,
though occasionally mistaken on western matters.)
Hodgkin, Thomas. Italy and Her Invaders, Vol. 6, The Lombard
Kingdom. Oxford: Oxford University Press, 1916. (Classic
account.)
Noble, Thomas F. X. The Republic of Saint Peter: The Birth
of the Papal State, 680–825. Philadelphia: University of
Pennsylvania Press, 1984. (Full bibliography through the
early 1980s.)
Richards, Jeffrey. The Popes and the Papacy in the Early Middle
Ages, 476–752. London: Routledge and Kegan Paul, 1979.
Martin ArbagiLEO IX, POPE (1002–1054)
Pope Leo IX was born as Bruno of Egisheim in 1002
into a noble Alsatian family. His early studies were at the
regional center in Lorraine of Toul, where, in 1017, he
became a canon at the cathedral. Related to the German
ruler Conrad II, he served prominently in the royal army
in Lombardy in 1026. Conrad appointed him the bishop
of Toul in 1027. Inspired by the monastic reform efforts
of the tenth and eleventh centuries, Bruno sought to
bring the fruits of these movements to such monasteries
in his diocese as St. Aper, St. Dié, Moyenmourier, and
Remiremont. Reform of the diocesan clergy also was
the order of a number of the synods he held. His efforts
to reinvigorate his diocese as the bishop of Toul would
prepare him for extending these activities to the whole
Western Church when he became pope.
The emperor Henry III, his cousin, selected him to be
pope in 1048, after the brief reigns of Henry’s previous
two appointees, and he was crowned at St. Peters with
the acclamation of the Roman people. From Lorraine he
would summon such like-minded reformers as Humbert,
abbot of Moyenmoutiers; Frederick of Liege, the futureLEO III, EMPEROR