James was born in the Palace of St James, London, and spent most of his childhood in and around the great city. Like Charles, he participated in the English Civil War, and was almost captured by Parliamentary forces at the Battle of Edgehill (1642). Not safe in England, he escaped to the Continent and remained there until it was safe for him to return. When his brother was recognised as King following the Restoration of the monarchy in 1660, James was recognised as next in line to the throne.

James duly became King at his brother's death on 6 February 1685, but he only reigned for three years. In the late 1660s he had converted to Roman Catholicism, a move that had made him very unpopular in England. Ever since the reign of Elizabeth I, Roman Catholicism was seen as a threat to the liberty of Protestant England. Within months of his accession to the throne, his Protestant nephew, James, Duke of Monmouth (illegitimate son of Charles II) made at attempt to gain the throne. The Duke was proclaimed King by Protestant supporters, but he was defeated at the Battle of Sedgemoor (1685). The Duke was captured and executed for treason. Many of his supporters were also punished, either by death, transportation, or imprisonment.

James married twice. He was first married to Anne Hyde, daughter of the Duke of Clarendon, and then to Italian Mary of Modena. While his marriage with Anne was a love-match, a marriage that he went to great lengths to secure, like his brother he kept a number of mistresses. Unlike his brother, however, he had a number of legitimate children. By Anne he had eight children (four son, four daughters) and by Mary he had seven children (two sons, five daughters). Of the eight children he had with Anne, only two survived to adulthood: the two future queens, Queen Mary II and Queen Anne. As James had no legitimate male heir when he became King, his daughter Mary (married to her cousin, William of Orange) was next in line to the throne.  The promise of a Protestant succession made a Roman Catholic monarch tolerable, but in 1688 James's wife gave birth to a son: James Francis Edward. 

The birth of a male heir was fatal to James's sovereignty. In what is known as The Glorious Revolution of 1688, James II was deposed by his cousin and son-in-law, William of Orange. Not only did William have a claim to the throne as a grandson of Charles I, but as Mary's husband. William and Mary were recognised as joint-rulers by Parliament, and James was once again forced into exile. He tried to reclaim the throne at the Battle of the Boyne (1690) in Ireland, but was heavily defeated. He returned to France and died there in 1701.

As James's legitimate son, James Francis Edward believed that he was now the rightful King of England, but he never achieved the crown. As he claimed to be the rightful King, he became known as The Old Pretender. His son, Charles, who also asserted his right to the crown, became known as The Young Pretender. But when Queen Anne died without an heir in 1714, the crown passed to George Hanover, great-grandson of James I.

While James II is one of England's least known kings, being in death as he was in life overshadowed by his elder brother, Charles II, his life was just as dramatic as some of England's more famous monarchs.