Agatha's parents are not proven to my satisfaction.  I cannot tell why she was sometimes known as "of Hungary."

  "The Plantagenet Ancestry," W.H.Turton (Balt.: Gen.Pub.Co., 1968) identifies Agatha "of Germany" as dau. of Bruno of Germany, Bishop of Augsburg and brother of Emperor Henry II.  Ernest-Friedrich Kraentzler, "The Ancestry of Richard Plantagenet and

Cecily de Neville," p. 58, states that Agatha is daughter of Ludolph von Braunschweig, Count im Derlingo, Marquis von Westfriesland, b. 1008, d. 04-23-1038, m, 1020 Gertrude von Egisheim.  See Szabolcs de Vajay, "Agatha, Mother of St. Margaret, Queen

of Scotland," in Duquesne Review, vol. 7, no. 2, Spring, 1962, pp. 71-80, with tables.

   "Ancestral Roots of Certain American Colonists...," Frederick L. Weis, 7th Edition (Baltimore: Genealogical Publishing Co., 1992), p. 2, gives the current status of the discussion of Agatha's parentage:  "For her ancestry, see The American

Genealogist 54:231.  But see also Frank Barlow, "The Feudal Kingdom of England, 16-17; Ritchie, "The Normans in Scotland," 389-392, and Szaboles de Vajay, [referenced above - AEM ] The parentage suggested in the last [i.e. de Vajay] reference is the

most probable.  See also Gabriel Ronay, "The Lost King of England" (1989), 117-121."

  In "The Saints of the Catholic Church" it is written that she was a sister of Gisela of Bavaria who was married to king (St) Sthephen of Hungary (he died August 5th 1038).

  Note:  Europ 

Alfred was one of the greatest military leaders in history; crowned at

Winchester Cathedral in 871; founded the British Navy; a scholar, etc.  The

Mercian kingdom ended during his reign "and in 886 Alfred's authority was

accepted by all Englishmen who were not under the power of the Danes.  From

this time onward the history of Wessex is the history of England."

{-Encyclopaedia Britannica, '56, 23:520; cf.8:483. Primary source is "Life

of King Alfred," Bishop Asser, trans. L. C. Jane (London: Chatto & Windus

Ltd., 1924).}

        ----- Compton's Encyclopedia (America Online, 1995) records:

ALFRED THE GREAT  (848?-899). The course of English history would have been

very different had it not been for King Alfred. He won renown both as a

statesman and as a warrior and is justly called "the Great."

   The England of Alfred's time was a country of four small Saxon kingdoms.

The strongest was Wessex, in the south. Born in about 848, Alfred was the

youngest son of Ethelwulf, king of Wessex. Each of Alfred's three older

brothers, in turn, ruled the kingdom. Alfred was by temperament a scholar,

and his health was never robust.

   Nevertheless in his early youth he fought with his brother Ethelred

against Danish invaders. Alfred was 23 when Ethelred died, but he had already

won the confidence of the army and was at once acclaimed king in 871. By this

time the Danes, or Vikings, had penetrated to all parts of the island. Three

of the Saxon kingdoms--Northumbria, Mercia, and East Anglia--had one after

another fallen to the Danish invaders.

   Under Alfred's leadership, the Saxons again found courage. The worst

crisis came in the winter of 877, when the Danish king, Guthrum, invaded

Wessex with his army. In 878 Alfred was defeated at Chippenham, where he was

celebrating Christmas, and was forced to go into hiding.

   A few months later he forced Guthrum to surrender at Chippenham. The Danes

agreed to make the Thames River and the old Roman road called Watling Street

the boundary between Alfred's kingdom and the Danish lands to the north. The

treaty, however, did not assure permanent peace. The Danes assaulted London

and the coast towns repeatedly. In about 896 they finally admitted defeat and

ceased their struggle for a foothold in southern England.

   Alfred was much more than the defender of his country. He took a keen

interest in law and order and was concerned with the improvement of the

cultural standards of his people. He encouraged industries of all kinds and

rebuilt London, which had been partly destroyed by the Danes. He collected

and revised the old laws of the kingdom. He invited learned men from other

countries to instruct the people because even the clergy of Wessex no longer

knew Latin, the international language of the church. He established a school

similar to the Palace School of Charlemagne.

   The "books most necessary for all men to know" were translated from Latin

into English so that the people might read them. Alfred himself took a part

in preparing the translations. The `Anglo-Saxon Chronicle' was probably begun

under his direction.

   Alfred died at the age of about 51 in 899. He was in no sense a true king

of England, for he ruled less than half of the island. After his death,

however, his capable son, Edward the Elder, and his grandsons extended their

rule over all of England.

 - - - - -

From an Internet article at Ancestry.com:

  "A British and U.S. archaeological team believes it has found the grave of

King Alfred, the great Saxon king, best remembered for fighting off the Danes

in the ninth century. As then befitted a king of great piety, Alfred was

buried in 899 at the New Minster church in Winchester, 65 miles southwest

of London. His remains are thought to have been moved 200 years later to

Winchester's Hyde Abbey, one of the great medieval monasteries. But the

abbey was destroyed in 1538, and the site believed to be Alfred's tomb now

lies next to a parking lot."