Crisis of 1469–1471
On 20 March 1469 the Queen gave birth to another daughter, Cecily, which caused serious concern to the King and made him think that his eldest daughter Elizabeth would rule the country after him. A year earlier, rumors had spread at court about an aggravation of enmity between the supporter of the King, the Earl of Warwick and the Queen, whose numerous relatives moved the Earl from court. In that same year, 1468, a final split occurred between Edward IV and Warwick due to the marriage of the King's sister Margaret: Warwick, who had once failed to marry the King to a French princess, wanted to conclude an alliance with France through the marriage of Margaret and a French prince, but Edward IV, following the advice of the Woodvilles, married off his sister to an enemy of France – Charles, Duke of Burgundy, whom Warwick hated and despised. In 1469, a feud between Warwick and the royal couple led to an alliance between the Earl and the King's younger brother, George, Duke of Clarence, whose position as heir to the throne was threatened by the idea of Edward IV appointing his eldest daughter as his successor.
Earlier, even at a time when the King was close to Warwick, the Earl wanted to marry his daughters Isabella and Anne, who were the richest heiresses in England, to the King's brothers, but Edward IV refused him, fearing the rise of the Nevilles. In July 1469 Clarence openly disobeyed his brother by marrying Warwick's eldest daughter at Calais; then both of them landed with troops in England and announced George's claim to the English throne, declaring Edward IV was illegitimate, born of Cecily Neville's affair with the English archer Blaybourne. At this time, Mary's mother, along with at least two daughters, one of whom was Elizabeth, visited Norwich, where they were received with magnificent celebrations and theatrical performances; It is not known for certain which of the two younger princesses at that time accompanied her mother, however, it was probably Mary, since Cecily was too small. The Queen and princesses were settled in the house of the monk-preachers; here the royal family received news that Warwick had not only won the Battle of Edgcote, but also captured the King, and also executed without trial Mary's maternal grandfather and uncle, Earl Rivers and John Woodville. It is not known how the grandfather's death affected the little princesses, but most likely the Queen hid what happened from the children. At the same time, Mary's maternal grandmother, Jacquetta of Luxembourg, was arrested after being accused of witchcraft and the use of love spells of the King. Although Jacquetta was acquitted, this unpleasant episode, as well as the unmotivated execution of Earl Rivers, showed how far the enemies of Edward IV were ready to go to destroy his wife and her family. Despite all this, the Queen herself and her daughters were not harmed during Warwick's brief rise, except that Mary's mother was assigned a reduced staff of servants.
By the autumn of 1469, Edward IV managed to gain freedom and already in September he entered London in triumph, where he began to lure the nobles back to his side. In the winter of 1470, the King regained full control of the government and declared Warwick and Clarence traitors; both of them fled to France, where by July 1470 Warwick managed to conclude an alliance with the former Queen Margaret of Anjou, who wanted to put her husband or son on the throne; as a part of the alliance, the former Prince of Wales married Warwick's second daughter. In September 1470, Edward IV prepared for an invasion by the combined forces of Warwick and Margaret of Anjou. For their safety, Mary, her sisters, and her mother were moved to the Tower of London. Anticipating a future crisis, the Queen ordered the Tower to be fortified and security increased. Elizabeth Woodville was in her seventh month of pregnancy and a maternity ward was prepared for her, but she failed to use it: Warwick invaded England, and in early October news appeared in London that Mary's father, along with his younger brother Richard, Duke of Gloucester, had fled the country, having only an illusory hope for a return. On 6 October Warwick and Clarence entered the City of London, and King Henry VI was formally re-enthroned.
Having received news of her husband's fall, Queen Elizabeth, along with her mother and three daughters, including Mary, hurriedly left the Tower in the middle of the night on a barge and arrived in search of refuge at Westminster Abbey, where she was known as a very pious woman. When the royal family arrived at the hideout, the Abbey was nearly empty; the Abbot of Westminster Thomas Milling took them under his protection –a kind, hospitable man, he did not want to place the Queen and princesses with criminals and gave them his house at the western entrance to the Abbey, where there were three rooms and everything necessary for the convenience of the royal family. Also, they were assisted by ordinary Londoners: the butcher John Gould donated half a cow and two sheep a week to the family of King Edward IV, and the fishmonger provided them with provisions on Fridays and fasting days.
While in hiding, the princesses spent most of their time with nannies, as Queen Elizabeth was busy with the birth and subsequent care of Prince Edward, who was born in early November 1470. Mary and her family spent another five months in the shelter. In April 1471, the princess's father, spurred on by the news of the birth of his son, returned to England and, first of all, after attending a thanksgiving service in Westminster Abbey, took his family out of hiding. On the same night, Mary, along with other family members, was transported to Baynard's Castle, which served as the residence of her paternal grandmother, Cecily Neville. On 11 April, the Queen and her children, accompanied by the King's mother, the Queen's brother Anthony Woodville, and the Archbishop of Canterbury Thomas Bourchier, set out for the Royal Apartments in the Tower of London, while Mary's father went north to reclaim the crown. On 14 April, Warwick was killed at the Battle of Barnet, and on 4 May Edward IV finally defeated the Lancastrian troops at the Battle of Tewkesbury, in which the Lancastrian heir Edward of Westminster was killed and Margaret of Anjou was captured. However, on 12 May, while Edward IV was still on his way to London, the last supporters of the House of Lancaster organized an attack on the Tower, intending to restore Henry VI to the throne; two towers were fired from the river, in one of which was Mary and her family. The attack was repulsed, but this forced Edward IV to put his predecessor to death, and on 21 May 1471 Henry VI was murdered in his dungeon.