The reign of Henry IV lasted from 1399 to 1413. The hereditary heir to the Crown on the death of Richard II was a child, Edmund Mortimer, Earl of March, and he was detained a prisoner at Windsor Castle during the whole of Henry's reign, and only liberated by Henry V in 1413. There was at least one fight in Berkshire during the time of Henry IV. In 1400 an attempt was made by some of the nobles to fall on the King at Windsor, but he was warned in time, and retired to London, and when the insurgents reached Windsor, they entered the Castle without opposition, searched for the King, but found he had gone. Meanwhile he had raised a force in London, and came to attack the insurgent nobles, who retreated, and a sharp encounter took place at Maidenhead Bridge. The insurgents retired to Oxford and were eventually defeated. James I, King of Scotland, was a prisoner at Windsor during most of the last ten years of his long captivity, which ended by his release in 1424. His book, The King's Quhair, was written at Windsor, and it was at Windsor that he fell in love with Jane Beaufort, who afterwards became his Queen. Henry VI was born at Windsor in 1421, and became King when about nine months old. He grew up weak in mind, and during his reign all England was involved in the Wars of the Roses. Berkshire was during most of the time held by the Lancastrian party, but in 1460 Newbury was taken by the Earl of Wiltshire on behalf of the Yorkists. In the next year, 1461, the Duke of York obtained the Crown under the name of Edward IV. Henry VI held several Parliaments at Reading, and Edward IV also visited the Abbey, and it is recorded that in 1464 he made the first public announcement of his marriage with Elizabeth Woodville at a great Council of the Peers at Reading. The marriage was not popular, and it was especially disliked by the Nevilles, the most powerful of whom, Richard Earl of Warwick, subsequently defeated Edward's forces and restored Henry VI, but Henry's renewed reign lasted only some six months, for Edward defeated Warwick, who was killed, at the battle of Barnet in 1471. Warwick and his brother the Marquis of Montagu, also killed at Barnet, were both buried at Bisham Abbey in Berkshire. The greater part of St George's Chapel in Windsor Castle dates from the reign of King Edward IV, and he was the first of our kings to be buried there, 1483. The body of his rival Henry VI was removed to Windsor from Chertsey Abbey in 1484. The beautiful Rutland Chapel in St George's Chapel was built by Sir Thomas St Leger in memory of his wife Ann, sister of Edward IV. St Leger was beheaded by Richard III, but was buried in the chapel and a brass to himself and his wife still remains on the wall there.