Question: How many years is the reign of this King of England, who was remebered by his relationship with Catherine Grandison, Countess of Salisbury?

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History of Lacock: Lacock was first mentioned in the Domesday book in 1086 with a population of less than 200; with two small mills and a vineyard.  The village's main attraction Lacock Abbey was founded on the manorial lands by Ela, Countess of Salisbury and established in 1232; in the reign of King Henry III.  Lacock was granted a market and developed a thriving wool industry during the Middle Ages.  Reybridge, and a pack horse ford, remained the only crossing points of the River Avon until the 17th century.

Edward III of England: Edward III (13 November 1312 – 21 June 1377) was King of England from 25 January 1327 until his death; he is noted for his military success and for restoring royal authority after the disastrous and unorthodox reign of his father, Edward II.  Edward III transformed the Kingdom of England into one of the most formidable military powers in Europe.  His long reign of 50 years was the second longest in medieval England and saw vital developments in legislation and government—in particular the evolution of the English parliament—as well as the ravages of the Black Death.

Paston-Bedingfeld baronets: The Bedingfeld, later Paston-Bedingfeld Baronetcy, of Oxburgh in the County of Norfolk, is a title in the Baronetage of England.  It was created on 2 January 1660 for Henry Bedingfeld, a cavalier, in recompense for his losses in the Royalist cause during the Civil War, when he fought as a Captain in King Charles 1st's armies, and Interregnum years, computed at £47,194 18s 8d, or well over £3,150,000 in later-1990s terms.  The Bedingfelds are said to descend from 'Ogerlis', a Norman, who, in 1100, held land at Bedingfield, Suffolk.  His descendant, Edmund Bedingfeld, married Margaret (died 1446), daughter and heiress of Sir Robert Tuddenham (and sister and co-heir of her brother Sir Thomas Tuddenham, executed in 1462), bringing to her husband estates including the manor of Oxburgh, near Swaffham, Norfolk.  The sixth Baronet married Margaret Anne, daughter and heiress of Edward Paston.  In 1830 he assumed by Royal licence the additional surname of Paston.  The eighth Baronet was a Major in the 3rd Battalion of the Liverpool Regiment, and served in the Second Boer War.  The present Baronet is a co-heir to the ancient barony of Grandison, which has been in abeyance since 1375.  Henry Paston-Bedingfeld, the noted officer of arms, is the 10th baronet.

Katherine Swynford: Katherine Swynford, Duchess of Lancaster (November 25, 1350 – May 10, 1403) (also spelled Katharine or Catherine), was the third wife of John of Gaunt, Duke of Lancaster, a son of King Edward III.  She had been the Duke's lover for many years before their marriage.  The couple's children, born before the marriage, were later legitimated during the reign of the Duke's nephew, Richard II.  When the Duke's son from his first marriage overthrew Richard, becoming Henry IV, he introduced a provision that neither they nor their descendants could ever claim the throne of England.

John de Montagu, 1st Baron Montagu: John de Montacute (  1330 –  1390 ) was a 14th-century English nobleman and loyal servant of King Edward III.  He was the son of William Montagu, 1st Earl of Salisbury by his wife Catherine Grandison, and younger brother of William de Montacute, 2nd Earl of Salisbury (1328–1397).  He also had several younger sisters.

Eleanor Holland, Countess of Salisbury: Eleanor Holland, Countess of Salisbury (1386- after 1413), was an English noblewoman, the daughter of Thomas Holland, 2nd Earl of Kent, a half-brother of King Richard II of England.  She was the first wife of Thomas Montacute, 4th Earl of Salisbury.  One of her brothers was Edmund Holland, 4th Earl of Kent, to whom she was co-heiress.  She is not to be confused with her eldest sister Alianore Holland, Countess of March who bore the same name.

Catherine Grandison, Countess of Salisbury: Catherine Grandison, Countess of Salisbury (c. 1304 – 23 November 1349) was an English noblewoman, remembered for her relationship with King Edward III of England and possibly the woman in whose honour the Order of the Garter was originated.  She was the daughter of William de Grandison, 1st Baron Grandison, and Sibylla de Tregoz.  Her mother was one of two daughters of John de Tregoz, Baron Tregoz (whose arms were blazoned "Gules two bars gemels in chief a lion passant guardant or"), maternal granddaughter of Fulk IV, Baron FitzWarin).  Catherine married William Montacute, 1st Earl of Salisbury in about 1320.

Edmund Mortimer, 3rd Earl of March: Edmund de Mortimer, 3rd Earl of March and "jure uxoris" Earl of Ulster (1 February 1352 – 27 December 1381) was son of Roger Mortimer, 2nd Earl of March, by his wife Philippa, daughter of William Montagu, 1st Earl of Salisbury and Catherine Grandison.

Shober Bridge: Shober Bridge is a historic humpback bridge carrying Ellis Street across the Norfolk Southern Railway in Salisbury, North Carolina, one of two timber bridges in the city.  It has asphalt on top of a wooden deck and has needed replacement for many years.  Currently, the Shober Bridge has a six-ton weight limit, meaning large trucks and emergency vehicles cannot use it.  Historic Salisbury Foundation calls it "a contributing structure to the Ellis Street Graded School Historic District and ... a gateway entrance to Salisbury proper."  It was named for Col. Francis Shober, who represented Salisbury in the United States Congress in the late 1860s.  In 1999, the Shober Bridge was named to the National Register of Historic Places as part of the Ellis Street Graded School Historic District.

James Harrington (Yorkist knight): Sir James Harrington, KB, MP of Hornby (? 1430 – 22 August 1485) was a prominent supporter of the House of York in Northern England during the Wars of the Roses, having been retained by Richard Neville, 5th Earl of Salisbury, who was brother-in-law to the head of the House of York, Richard of York.  He was second son of Sir Thomas Harrington, who had died with the king's father at the Battle of Wakefield in December 1460.  James himself had fought with Salisbury at the Battle of Blore Heath in 1459, where he had been captured and imprisoned by the Lancastrians until the next year.  He was a significant regional figure during the reign of King Edward IV, although the early years of the new king's reign were mared by a bitter feud between him and the Stanley family over a castle in Lancashire.  On the accession of King Richard III in 1485, he was appointed to the new king's Household, and as such was almost certainly with him at Battle of Bosworth two years later.  It is likely that he fell in battle there, although precise details of his death are now unknown.

Supporting paragraphs: Catherine Grandison, Countess of Salisbury Edward III of England
Answer: 50