Elizabeth was extremely well educated and was a precocious and intelligent child. She mercifully escaped the congenital syphilis passed by her father to his other children, and grew into a strong and healthy child who delighted in riding, hunting, archery and dancing and who became a proficient linguist. It was not until 1543 that Henry's last wife, Katherine Parr, brought all of the children together in a united household and proved an excellent stepmother. Whilst Elizabeth and Mary tolerated each other they never became close. Elizabeth always regarded herself as a rightful heiress. Though supportive of Edward VI, she was seen as a threat and a liability by Mary when she became queen in 1553. Elizabeth had been raised within her father's newly reformed Church of England while Mary remained defiantly Catholic. During Mary's reign there were terrible persecutions of the reformers after years of ardent Protestantism in Edward's reign. Mary even believed that Elizabeth had plotted against her in a number of conspiracies and had her sister confined first to the Tower of London and then to Woodstock, near Oxford. Thus, when Edward and Mary both died childless, it was with much relief and a belief by Elizabeth that "this is the Lord's doing," that she inherited the throne. Her accession was welcomed throughout the land.

Elizabeth had all the credentials for a strong queen. She inherited much from her father, her physical strength and resolution, her vicious temper, her cruelty, but also a delight in pomp, a passion for power and a general joy of life. From her mother, apart from her youthful beauty, she inherited a degree of insincerity and a tendency towards jealousy. She also had an interest in astrology, consulting the alchemist John Dee over the most propitious date for her coronation. His forecast evidently worked, for not only did Elizabeth go on to reign for nearly forty-five years, longer than any king since Edward III, and also live longer than any English monarch, but her reign was undoubtedly the most glorious England had seen and one which firmly established England as a world power.

Elizabeth's first pressing responsibility was to resolve the religious division in England. She did not want a backlash against the Protestant persecutions of Mary's reign, but neither did she want the rampant Protestantism of Edward's. She sought to strike a balance, accommodating both religions, so that although Protestantism became the national religion, she did not regard it as wrong if there were those who wished to hear the Roman mass in private. But she disliked the more extreme Calvinist tendencies in Protestantism. Those who acted wisely would be safe in Elizabeth's realm, but she would not tolerate any who sought to test her will. Nevertheless, throughout her reign there were many Catholic conspiracies seeking to overthrow Elizabeth. This became worse after 1570 when the Pope, tired of seeking Elizabeth's compliance to the authority of Rome, issued a bull deposing her.

Since she took no notice of this, it only strengthened her role as "Supreme Governor of the Church of England" and meant that anyone who continued to practice Catholicism was effectively a traitor. Much against her own wishes, religious persecution returned after 1570 and this only aggravated the Catholic cause against her. This in turn widened the rift between England and Scotland and led to the darkest shadow cast over her reign, the treatment of Mary Queen of Scots, her cousin and a claimant on the English throne.

The relationship between Scotland and England had been one of near constant hostility for a thousand years. Mary of Scotland was still in her teens when Elizabeth came to the throne, but as the queen consort of the king of France she exerted authority in two strong Catholic countries. Mary's mother, Mary of Guise, who was the queen regent in Scotland, was an even more ardent Catholic and it was her desire to place her daughter on the English throne. There were many Scots who feared that Scotland would become a puppet state of France, and the growing number of Protestants made Scotland a land divided. Elizabeth took advantage of this, secretly supporting the Scottish Protestants in their work against the two Maries. The Scottish rebels soon became too powerful to overlook and Mary of Guise sought aid from France. A French invasion became a probability, and advance troops landed in Scotland. Elizabeth was able to use this situation, albeit reluctantly, to enter into an alliance with Scotland in February 1560 (Treaty of Berwick), whereby England promised troops to help repel the French. Despite some rather scrappy fighting by the English, the French decided to negotiate, circumstances hastened by the death of Mary of Guise. The Treaty of Edinburgh was signed on 6 July. Five months later Francois II of France died and in August 1561 the widowed Mary returned to her native Scotland, much to the horror of the English who had hoped she would stay in France. Her power there had been eclipsed by the rise of Catherine de Medici, mother of the young king Charles IX, and Catherine had no love for the Guises. Whilst this helped Anglo-French relations, Mary's return to Scotland might have stirred up old rivalries. In August 1560 the Scottish Parliament had abolished the pope's authority and brought its Protestant church more in line with England's, but Mary remained a Catholic. To her credit, Mary was conciliatory and her charm captivated her Scottish subjects who soon welcomed her return. However, she refused to ratify the Treaty of Edinburgh, the terms of which would have denied her any possible succession to the English throne, and she actively sought to be regarded as Elizabeth's heir presumptive in the absence of any children. Plans for a meeting between Mary and Elizabeth nearly came to fruition in August 1562, but the eruption of civil war in France between the Catholic Guises and the Huguenots (Protestants) made the situation too tense. It was the closest Elizabeth and Mary ever came to meeting. Aggravatingly Elizabeth refused to name a successor, even after a near fatal bout of smallpox in October 1562, always maintaining that although she had no desire to marry, for the sake of the succession one day she would and produce an heir. Mary of Scotland, on the other hand, was actively in pursuit of a new husband and there was fear in England that if she married the heir of a strong Catholic country, she would have the power to invade England and oust Elizabeth. This was made all the more potent when negotiations opened between Scotland and Spain for the marriage between Mary and the heir, Don Carlos. These only ceased when Don Carlos was declared insane. Mary however lost her controlling hand when she fell in love with her cousin, Lord Darnley. The marriage proved unpopular and the subsequent events, including the murder of Mary's secretary, David Rizzio, the mysterious death of Darnley in February 1567 and Mary's affair with and rapid marriage to Lord Bothwell, brought about the fall from grace of Mary and her subsequent deposition. From July 1567 Mary was a captive, and in May 1568 she was driven out of Scotland and threw herself upon Elizabeth's mercy. Elizabeth was outwardly supportive but maintained she could not harbour Mary while the stigma of her involvement in the death of Darnley was unresolved. Mary remained in prison, first at Carlisle, and then in a series of castles in northern England. This continued for nineteen years with the inevitable consequence that Catholic factions used Mary as the figurehead for their cause. There were several conspiracies during this period, culminating in the Babington Plot in the summer of 1586. Plans were well advanced for the murder of Elizabeth and there were hopes of a Spanish invasion, when Babington was betrayed. Mary was aware of Babington's schemes and as a consequence was herself tried for treason, found guilty and, with much reluctance on Elizabeth's part, executed. At this same time Elizabeth had bestowed a pension upon Mary's son, James VI, in effect recognizing him as her heir.

Just why Elizabeth did not marry is the matter of some conjecture. Her dedication to the throne and her people led her to say that she was married to the nation in much the same way as she believed her bishops were married to the church. She expressed a low opinion of any bishop who chose to marry. Her own haughtiness and belief in her absolute authority almost certainly meant she would have found it difficult to share government with anyone, for although she might remain queen, any husband, especially one of the proper status, could not have been denied his views. It was more a problem over whom to marry rather than whether to marry, and that problem was never resolved. It was not helped by the fact that Elizabeth's first love was almost certainly her favourite - Robert Dudley, earl of Leicester, the brother of Guilford Dudley, husband of Lady Jane Grey. Dudley was already married, to Amy Robsart, whose mysterious death in 1560 caused many to believe that Dudley had murdered her. Thus tainted, Dudley was no suitable candidate as Elizabeth's husband, even though he pursued his suit for the next twenty years. He remained something of a philanderer and adventurer and died in 1588. Elizabeth was much saddened by his death for although she had other court favourites, such as Sir Christopher Hatton, the captain of the bodyguard, and, most notably, Robert Devereux, earl of Essex, the flame burned strongest for Dudley and he never left her heart.

Nevertheless Elizabeth recognized that a political marriage was necessary both for producing an heir and for strengthening England's position in Europe, but she constantly prevaricated over her choice, using it for political bargaining. For a period she had to be the most eligible spinster in Europe, and various royal families made their approaches. Early in her reign there had been negotiations with Philip II of Spain, the former husband of Elizabeth's sister Mary, but these were dropped when Elizabeth confirmed her opposition to papal sovereignty in 1559. The main contender then became Charles, the archduke of Austria, and younger son of the Holy Roman Emperor Ferdinand. He was an ideal candidate and, had Elizabeth been given more support from her brilliant and long-suffering adviser, William Cecil, the marriage might have happened. But Cecil counselled against it, Elizabeth became more involved with Dudley and negotiations collapsed in 1567 on religious grounds. By the time Elizabeth came to reconsider Charles in 1570 he was betrothed to another. Now approaching 37, Elizabeth's eligibility was failing. If she was going to marry she needed to marry soon. Negotiations opened with Henri, duke of Anjou, the younger brother of Charles IX, king of France (who had also been a suitor at one stage). Negotiations again failed on religious grounds and so Anjou's younger brother Francois, duke of Alencon, stepped into the frame. The age difference between the two was considerable, and it was not helped by the fact that the French persecution of the Huguenots aggravated the Anglo-French religious balance. Nevertheless Elizabeth apparently became enchanted with the diminutive young Duke, whom she nicknamed "frog" when she first met him in 1579. Though negotiations were erratic Elizabeth caused a sensation in November 1581, when she announced that she would marry him. This was really a ploy on Elizabeth's part to increase her bargaining power with the French, as she was not that sincere in her proposals to marry. All came to naught in 1584 when Alencon died. He was the last serious suitor for by now Elizabeth was past the age of successfully bearing a healthy child. It is almost certain that despite her many favourites, Elizabeth remained a virgin all her life. She actually delighted in her virginity, deploying it as a strength, and became known as "the Virgin Queen". Walter Raleigh, another court favourite, named the territory in North America Virginia in her honour in 1584. Elizabeth refused to acknowledge that she was ageing. She wore a wig (as she had lost much of her own hair), whitened her face to hide the scarring from the smallpox, and even rubbed urine into her face to remove wrinkles. She could not hide her blackened teeth arising from her love of sugar.

During all these years England had been fighting an unofficial conflict with Spain. Philip II of Spain was infuriated by England's blatant piracy of Spanish ships from the New World. Spain and Portugal dominated the seas, and in 1580 Philip became king of Portugal as well as Spain, thus increasing his maritime and merchant strength. In 1493 the then pope had partitioned the New World between Spain and Portugal and now the bounty of the Americas was united in Philip. Spain had exerted on an exploitation of the New World, forbidding other countries access to the lands. In 1562 an English seaman, John Hawkins, had found a way round this by trading directly with the Spanish in Hispaniola over slaves. The venture proved profitable and two more followed, this time with Elizabeth as a shareholder, but the third expedition fell foul of the Spanish and only just limped home in early 1569. Hawkins's fellow captain, Francis Drake, now regarded it as open season on the Spanish and from 1572 he began to plunder Spanish enterprises in Central and South America. By 1577 Drake had been introduced to Elizabeth and she unofficially encouraged his activities against Spain. In December 1577 Drake set off on what would become his voyage around the world, plundering Spanish vessels in both South America and the East Indies. It has been estimated that the total value of Drake's booty was worth about £450,000, which would be many millions at today's rates. He returned to England in September 1580 and became a national hero. He was knighted in April 1581.

Philip's relationship with England continued to sour. England's support to the Netherlands against Spain was the final straw in 1585. After the execution of Mary Queen of Scots, Philip believed he had a divine right to invade England, a major heretical aggressor, and contended that he had a claim on the English throne, because he was distantly descended from Edward III. In July 1587 Philip secured a treaty with the pope approving the conquest of England, provided that the land was restored to Catholicism. The pope allowed Philip to choose whomever he wished as England's ruler. While these negotiations were in hand Drake led a punitive expedition into Spain, capturing and destroying many Spanish vessels. The culmination of all this was one of the most famous confrontations of all time when Philip sent his apparently invincible Armada against England in July 1588. Philip's venture was doomed by the weather even more than by the superiority of English seamanship and the better design of the English ships, which allowed them to hug the water and dart through the waves. By comparison the huge and imposing Spanish galleons were a liability in strong winds. Although Elizabeth had hesitated at first about the confrontation with the Armada, the defeat of Spain's might was one of the most important victories in English history. Conflict with Spain dragged on for another fifteen years. In April 1596 the Spaniards turned up on Elizabeth's doorstep by capturing Calais. A joint Anglo-Dutch offensive was made against Spain under the command of Essex. It captured and plundered Cadiz, destroying much of the fleet, and returning home rich with booty, little of which the queen saw as most of it ended up in the hands of the looters. Philip despatched a second Armada in October 1596, but this again fell foul of the weather as did, this time, the English fleet. This was the last major battle against Spain although hostilities continued beyond Philip 11's death in September 1598, and even beyond Elizabeth's.

The end of the century saw England at the height of her power. Her great sea captains and explorers - Francis Drake, Walter Raleigh, Martin Frobisher, and John Hawkins - meant that she effectively "ruled the waves". Literature blossomed – this was the age of Francis Bacon, William Shakespeare, Christopher Marlowe, Sir Philip Sidney and Edmund Spenser, who’s Faerie Queen (first part, 1589; second part 1596) was dedicated to Elizabeth. Scientific study did not advance quite so quickly in England as it did in the Protestant parts of Europe, but there were some great physicists and speculative thinkers who emerged in Elizabeth's time, with Sir Francis Bacon again head and shoulders above them.

The last drama to be enacted during Elizabeth's reign was the revolution in Ireland and the subsequent fate of the earl of Essex. Hugh O'Neill, earl of Tyrone, had been in rebellion against the English for some years, and this reached a climax in August 1598 when O'Neill massacred an English force sent to relieve the fort at Blackwater. The Irish were now in open revolt and England sent in an army. The Earl of Essex jumped at the opportunity to take command, hoping that this might restore his favour with the Queen, who had been cold to him since Essex had quarrelled with her ministers William Cecil, now Lord Burghley, and his son Robert over the possibility that Elizabeth might negotiate for peace with Spain. This had followed an alleged assassination plot against the queen organized by Rodrigo Lopez, a Portuguese Jew supposedly in the pay of Philip of Spain, and involving Ferdinando Stanley, king of the Isle of Man. Elizabeth had some suspicions that Essex had concocted the whole story in order to get back into her favour. Many did not believe that Essex was a capable commander, but the queen supported him and gave him all the men and finances he needed. Elizabeth would have been only too happy to be rid of Ireland, except that she feared it falling to a foreign power, especially to Spain. There had been other rebellions during her reign, that of Sliane O'Neill in Ulster during the 1560s, the Fitzmaurice rising of 1569-73 and the Desmond rebellion of 1579-83. These received harsh retaliation from the English, slaughtering young and old alike and keeping the island savagely repressed. Elizabeth had hopes that Essex might similarly subdue the rebels, but instead he spent the summer of 1599 moving about the island and achieving little. He negotiated terms with O'Neill, after losing more than half his force to the unhealthiness of the Irish environment, and returned home without permission. Essex expected to be regarded as a hero, but instead the queen and the Privy Council showed him nothing but contempt. Essex was censured and humiliated. Essex sought his revenge upon the Council, but was caught and tried for high treason and executed in February 1601. Although Elizabeth was saddened by Essex's death, she was delighted when his successor in Ireland, Lord Mountjoy, succeeded in defeating Tyrone in December 1601 and in reaching an agreement with Spanish opportunists who had invaded Kinsale that September. Tyrone's eventual surrender was not received for another sixteen months.