218 Diaz, Bartholomew
Diaz, Bartholomew (Bartolomeu Dias)(ca. 1450–
1500)Portuguese sea captain who sailed around southern
Africa
The date, about 1450, and place of birth, as well as the
early life, of Bartolomeu Diaz or Dias are a mystery. He
was a respected navigator and trusted at court. In 1487
he was commissioned by King John II (r. 1481–95) to
continue the Portuguese voyages down the West African
coast seeking a route around it. Diaz sailed with a group
of three ships, including a supply ship and 50 to 60 men.
He also carried a good MAPcompiled by a Portuguese spy.
The supply ship was abandoned at Angra das Aldeias on
the coast of modern Angola and the other two caravels
sailed on south along the coast. Encountering strong
headwinds, Diaz sailed into the open Atlantic, where he
expected to find southerly winds. After two weeks, Diaz
turned north and west toward Africa again, unaware that
he had sailed far south of it. Encountering no land after
days, he turned north and, on February 3, 1488, sighted
the coast of Africa.
Since the coastline was headed east and north, he
guessed that he had rounded Africa. The ships reached
the Keiskama River and turned back as a result of near-
mutiny. On June 6, 1488, they returned to the tip of
Africa, which Diaz then named Cape of Storms. King
John later changed that to Cape of Good Hope.
Diaz returned to LISBONin December 1488, having
sailed approximately 16,000 miles in 15 months. He
opened a way by sea to the Indian Ocean that would free
PORTUGALof Venetian and Islamic MERCHANTS, an advan-
tage in international TRADE. Diaz’s trip also disproved
Ptolemy’s theory that Africa was linked to Asia. The
Indian Ocean was actually an inland sea. Diaz later joined
the expedition of Pedro Álvarez CABRALand was present
at the discovery of BRAZIL. He died when his ship later
sank during a storm near the Cape of Good Hope on May
23–29, 1500.
See alsoPORTUGAL;VASCO DAGAMA.
Further reading:Eric Axelson, Congo to Cape: Early
Portuguese Explorers,ed. John Woodock (London: Faber
and Faber, 1973); J. W. Blake, Europeans in West Africa,
1454–1578(London: The Hakluyt Society, 1937); Edgar
Prestage, The Portuguese Pioneers (London: Black,
1933).
Dictatus papae This consists of a manuscript text
from the registers of Pope GREGORYVII on the duties of
the reformed papal office. Under the title Dictatus papae,
or The Seventy-four Titles,these letters of Pope Gregory
VII dated from March 3–4, 1075. They list 27 proposi-
tions concerning the aspirations, privileges, and duties of
the PAPACY, assembling together texts asserting the rights
and prerogatives of the papacy over LATINCHRISTENDOM.
As a platform of action and intervention, the Dictatus
bore Gregory’s ambitious personal stamp. Its clauses stip-
ulated that the Roman church cannot err, and anyone not
a member of the Roman church could not attain salva-
tion. The pope could not be judged by anyone and his
sentences were irrevocable. The pope alone had a univer-
sal jurisdiction and could “create” new law. He could
depose or absolve bishops and send legates to preside
over councils, even if their status was below that of the
bishops present. He had a right to a series of privileges,
such as the unique control of the imperial insignia. The
pope could depose an emperor and release his subjects
from any oaths of loyalty. Such ideas formed the disputed
basis of papal pretensions to power for the rest of the
Middle Ages.
Further reading:Eamon Duffy, Saints & Sinners: A
History of the Popes(New Haven, Conn.: Yale University
Press, 1997); Walter Ullman, A Short History of the
Papacy in the Middle Ages(London: Methuen, 1972).diet See FOOD, DRINK, AND NUTRITION; FAMINE; FASTS,
FASTING, AND ABSTINENCE.digest See CORPUS IURIS CIVILIS.Dimitri of the Don (Dmitrii Ivanovich Donskoi)
(1350–1389)grand duke of Vladimir and Moscow
Dimitri was born in 1350, the son of Ivan II Ivanovich
(r. 1353–59), and succeeded his father at the age of
nine. In 1362 he was acknowledged duke of the region
of Vladimir by the TATA Rkhan. Fortifying MOSCOW,he
built the KREMLIN. Dimitri’s reign was marked by an
ultimately successful struggle to establish Moscow’s
hegemony over the other Russian principalities. Dimitri
encountered the opposition of the town of Tver and the
Lithuanians, who had attacked Moscow in 1368 and- He was able to force their withdrawal. In 1371 he
won the support of the Tatar khan and soon defeated
the Lithuanians.
By 1375 Dmitri was recognized as leader by the
Russian princes. After successful campaigns against the
Tatars, who had been raiding Russian lands, he turned
his efforts to MONGOLdomination. In 1380, on the plain
of Kuilokovo, Dimitri defeated the allied armies of the
Lithuanians and the Tatars. However, his victory was
soon avenged in 1381 by a general of TAMERLANE, who
invaded Russia, captured Moscow, and restored Mongol
power and authority. Dimitri was compelled again to
accept Mongol suzerainty, but he maintained local con-
trol and bequeathed the foundations of a powerful
dukedom to his son, Basil I (r. 1389–1425). He died in
Further reading:Robert O. Crummey, The Formation
of Muscovy, 1304–1613 (New York: Longman, 1987);
Janet Martin, Medieval Russia, 980–1584 (Cambridge:
Cambridge University Press, 1995).