I have a feeling she was an Essington, based on a few vague clues I've noticed while researching the Swynnertons. The merging of the Swynnerton and Essington fortunes likely came about through marriage, as was often the case in those times. The early Essington tree is not well represented on Geni (the earliest example I could find was from the late 16th century, Robert Essington ).
"In 21 Edw. III., 1347, John de Swynnerton paid the King for his relief for the Forest of Cannock and his other lands, all of which are specified in the Rolls, [he] being then described as Johannes de Swynnerton, filius et haeres Johannis de Swynnerton defuncti et Annae uxoris ejus, filiae Philippe de Montgomeris"
So Christiana's father-in-law (her husband's namesake) was married to Anna the daughter of Philippe de Montgomery.
"The Reliquary, Volume XXI (reprinted by the Swinnerton Family Society) has a nice pedigree chart for the family. In it we find that Christiana was the relic of Sir John Segrave at the time she married John de Swynnerton.
The Swynnerton family, including Sir Thomas, Richard, Humphrey, and -- John, were involved with Crecy or Calais, perhaps both (1346-7). As were the Montgomerys and many others, of course. A John Swynnerton was also appointed the King's escheator during the same years.
"Writ to the Treasurer and Barons of the Exchequer stating that the King's valettus, John de Swynnerton, Escheator of cos. Salop and Stafford, being in the service of the King abroad in the retinue of Sir Bartholomew de Burghersshe the father, was to be permitted to appear at the Exchequer by attorney to answer for the issues of his Escheatorship. Dated from Calais, 1st September, 21 E. III."
https://archive.org/details/collectionsforhi18stafuoft/page/148/mod...
https://archive.org/details/collectionsforhi18stafuoft/page/206/mod...
"In 22 Edw. III., 1348, [John de Swynnerton] purchased the manor of Essington, in the county of Stafford, from Robert de Essington, which was settled upon himself and Christiana his wife, to whom Roger son of Robert de Essington released all his title in 44 Edw. III., 1370-1."
From that I get that Roger Essington released all of his title to the property to Christiana, who must have been his sister. And John de Swynnerton must have gotten a sweet deal on the manor belonging to Robert de Essington because he married Robert's daughter.
"JOHN DE SWYNNERTON (II.) of Hilton, the son of John and Anna, who thus succeeded to the estates of his father and mother, was born about 1309."
"AN ACCOUNT OF THE FAMILY OF SWYNNERTON" pps.96-101 (concerning John de Swynnerton II, of Hilton).
https://archive.org/details/staffcollections07stafuoft/page/96/mode...
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A bio for Christiana's son (m. Clemency) on "History of Parliament":
https://www.historyofparliamentonline.org/volume/1386-1421/member/s...
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"Sir John de Swynnerton “de Hylton," the second Lord, like his father, was distinguished in the wars and politics of the period. Born in the year 1310, he inherited from his mother, Anne De Montgomery, the Seneschalship of the Royal Forest of Cannock, and the lordship of the manors of Hilton and Essington. He was also heir to lands in Repton, Melton, Tykenhall, Bolterford, Aldebrowe, and to Donnington, in co. Derby, as well as to certain rents in Lincolnshire.
For all these, as well as for Cannock Forest, held by Grand Serjeanty, he did homage to King Edward III., on his father's death in 1340. Later in life he established his right also to the ancient manor of Whelton, in co. Northants, which had belonged to the De Wheltons from the Conquest to the reign of Edward I.
Felicia de Whelton, Sir John de Swynnerton’s grandmother was in that reign left sole daughter and heiress of the last heir male. She, however, married a second time, and bequeathed the manor to her issue by her second marriage, Sir James Nevil, of Brampton, who dying without issue,
the manor reverted to Sir John de Swynnerton De Hilton.
Sir John de Swynnerton, in consideration of a deed apparently illegal, by which the widow of Sir James Nevil had conveyed the manor to John Holt, and Alice his wife, confirmed the grant in the year 1380, to the said John and Alice Holt, for their lives, and to their heirs and assigns for one year after, when the manor once more reverted to the heirs of Sir John de Swynnerton.
Sir John's wife was Christiana, relict of Sir John de Segrave, Kt., whom he married some time between the years 1340 and 1350, and who appears to have brought him an additional share of the manor of Repton.
This Christiana was connected, through her former husband and the De Hastings, with the old Earls of Chester, the last heir male of whom dying circa, 1232, left all his lands not in co. Chester to be divided among his four sisters and coheiresses. Of these lands the manor of Repton was part.
Sir John de Swynnerton was trained to arms under those two bold and impetuous spirits, Sir John (his father), and Roger, Baron Swynnerton, of Swynnerton, and shared with them in the earlier wars of Edward III. It was not, however, until his father died, that writs of Service were addressed personally to himself. In 1345 Letters of Privy Seal were directed to “Johannes Fitz Johan de Swynerton Armigero de Com. Staff,” [Staffordshire] which were tested by Lionel, the king's son, at Westminster, on July 4th, commanding him to appear with horses, arms, and men on the Feast of St. Lawrence (Aug. 12), at a place to be subsequently named in order to accompany the king across the seas to his possessions in France for the protection of his kingdom.
The campaign which ensued is memorable for the battle of Crecy, and the capture of Calais, on both which occasions Sir John de Swynnerton must have been present, together with Sir Thomas de Swynnerton, of Swynnerton, his first cousin.
He was probably knighted, as were many others on the field of Crecy itself, as about this time we find him no longer addressed as “ Armiger," but with the usual style of a knight.
In 1346 he was appointed King's Escheator of the co. of Stafford...
His wife, Christiana, was dead before 1380. He himself died on the Monday next after the Conception of the B. Virgin ( Dec. 8) 3 Ric. II. 1379. His inquisition was held at Hilton on Jan. 14, 1380, when it was found by the jury that he was Steward of the Forest of Cannock, and Lord of Hilton and Essington, and that John, his son, was his heir, and of the age of thirty years.
According to *Burke, or rather to a pedigree which appears in Burke, he left, as well as John, a son Thomas, styled “of Repyndon," who may have inherited land belonging to his mother, in the manor of Repton, and who is said to have died in 7 Hen . VI., 1429. This pedigree, however, is a concocted affair, and cannot be accepted as evidence.
"NOTES ON THE FAMILY OF SWYNNERTON, OF SWYNNERTON AND OTHER PLACES IN CO. STAFFORD" pps.34-38 and pps.97-99; pedigree chart pp.238-9, BY THE REV. CHARLES SWINNERTON, BENGAL CHAPLAIN (concerning John de Swynnerton II, "de Hylton")
https://www.google.com/books/edition/_/lKtDAQAAMAAJ?hl=en&gbpv=0
(This lengthy treatise on the Swynnerton family is continued through Volumes 20-21 and possibly others of the Reliquary.)
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[Christiana's father in law] married about the year 1309, the young heiress, Anne de Montgomery, to whom he had probably been betrothed from her infancy. Her father was Sir Philip de Montgomery, kt., the hereditary Seneschal of Cannock Forest, who died in 23 Edw. I., 1294, when Anne
was only three years old, and when in all probability she was left in the wardship of Sir Roger de Swynnerton of Swynnerton. Her mother was Felicia, daughter and heiress of Sir Nicholas de Whelton, kt., in co. Northants. Anne was their only child...
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Mr. De Mazzinghi and myself are agreed that these rents in Derbyshire, and especially in Repton, came to the [Swynnerton] family through the De Hastangs, but we differ, I think, as to the channel. Mr. De Mazzinghi attributes their accession to the marriage of the second Sir John de Swynnerton of Hilton, with Christiana, the relict of Sir John de Segrave, who appears to have been a son of that famous warrior, Sir John de Segrave, whom Edward I. left governor of Scotland after the capture of Stirling castle in 1804.
It happens that this John de Segrave, Christiana's first husband, had a relative of the same sirname, who married one of the heiresses of the De
Hastangs, part of whose property consisted of rents in Repton, and of course there is a possibility that the Swinnerton interest in Repton issued from this alliance.
But against this supposition, there is the notable fact that the first Sir John de Swynnerton, of Hilton, did himself die seized of rents in Repton, which his son's marriage would not account for.
I find here corroborative evidence of Burke's theory, that Sir John de Swynnerton [I, m. Anna de Montgomery] was a younger brother of Lord Roger de Swynnerton of Swynnerton Castle, and that they had both a common mother, Johanna de Hastang, daughter and heiress, or coheiress, of Baron de Hastang, Lord of Desirèe.
As a matter of fact, Johanna’s paternal manor of Desirèe went to her eldest son, by Sir Roger de Swynnerton the elder; and what so likely as that rents of hers in co. Derby should have fallen to Sir John de Swynnerton, a younger son, who became further enriched by his marriage with
the wealthy heiress, Anne de Montgomery?
This is, I think, the true solution of the difficulty, though at the same time, other rents in Repton may have accrued to the family by the marriage of Sir John de Swynnerton the younger, with Christiana de Segrave.
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So we're a little bit closer to identifying this Christiana (Unknown or Essington?) Segrave, Swynnerton's parents. I just have a strong feeling it might be either Robert or Roger Essington, and so far I've found nothing to dispute it. I just need to look for more proof. Meanwhile, these sources have yielded quite a bit of history on these 14th century nobles.
