Elizabeth was the only surviving child of Henry VIII and Anne Boleyn. At the time of her birth she was heir to the throne.
However, when Elizabeth was two-years-old, her mother was executed. A year later, a male heir, Edward, was born.
She only returned to her father's court when he married his sixth and final wife Katherine Parr. After Henry's death, she lived at her stepmother's home with her new husband, Thomas Seymour.
However, she left her home following an incident with Seymour. Although no one really knows what happened, it is thought Katherine found Elizabeth kissing him.
On King Edward's death of consumption in 1553, Elizabeth's sister Mary came to the throne, and Elizabeth was briefly confined to the Tower of London for suspected treason and collaboration with the rebel Thomas Wyatt. After a few months in the Tower, she was sent to Woodstock and placed under house arrest for a year. It was only when Mary I thought she was pregnant that Elizabeth was allowed to return to her Hatfield residence.
Mary's marriage to Philip II of Spain made it seem possible that an heir would be born, but Mary died childless in 1558. Elizabeth I was crowned Queen of England on 15 January 1559.
Elizabeth's 45-year reign - referred to as the Elizabethan era or the Golden Age of Elizabeth - was one of the more constructive periods in English history: literature bloomed through the works of Spenser, Marlowe and Shakespeare; Francis Drake and Walter Raleigh were instrumental in expanding English influence in the New World; Elizabeth's religious compromise laid many fears to rest and de-fused a potential powder keg; and fashion and education came to the fore because of Elizabeth's penchant for knowledge, courtly behaviour and extravagant dress.
One of the most important concerns during Elizabeth's early reign was religion. She relied primarily on Sir William Cecil for advice on the matter. The Act of Uniformity 1559, to which she gave assent shortly after ascending the throne, required the use of the Protestant Book of Common Prayer in church services.
Communion with the Catholic Church had been reinstated under Mary I, but was ended by Elizabeth as she assumed the title of "Supreme Governor of the Church of England", rather than "Supreme Head".
The Act of Supremacy 1559 was also passed, requiring public officials to take an oath acknowledging the Sovereign's control over the Church or face severe punishment.
Her cousin, Mary (Queen of Scots), was a Catholic but remained the most likely candidate to succeed her. When Mary was driven out of Scotland, she was received by Elizabeth but seen as a threat and so kept under lock and key at Fotheringhay.
Pope Pius V excommunicated Elizabeth in February 1570, something his predecessor had been reluctant to do. This made it impossible for Elizabeth to continue her policy of religious toleration.
Mary Stuart allowed herself to become implicated in yet another treason plot by Catholic sympathisers, and Elizabeth had her executed in 1587. This was the excuse that Philip II of Spain needed to make a determined invasion attempt.
Thanks to Elizabeth's naval leaders, notably Sir Francis Drake, the Spanish Armada of 1588 was defeated and scattered.
Elizabeth never married and became known as the 'Virgin Queen'. This is despite having many suitors throughout her reign, including her 'great love' Robert Dudley.
The pair were childhood friends and he soon became her favourite at court. They never married as Robert was already married to Amy Robsart when Elizabeth became queen. Amy died in mysterious circumstances - found at the bottom of the stairs - a few years later and the scandal meant the pair could never wed.
Despite this, Robert remained the queen's favourite until his death in 1588. She kept his last letter to her for the rest of her life.
Several foreign princes and dukes vied for the hand of Elizabeth, who successfully used their suits for developing a friendly relationship without accepting their hand. The man who came closest to marrying the queen was Francis, Duke of Alencon of France, but he died before negotiations were finalised.
Her death ended the Tudor dynasty. Elizabeth died on 24 March 1603, and is buried at Westminster Abbey.