Elizabeth of Bohemia in the context of "Thomas Percy (Gunpowder Plot)"

Elisabeth of the Palatinate (German: Elisabeth von der Pfalz; 26 December 1618 – 11 February 1680), also known as Elisabeth of Bohemia (Elisabeth von Böhmen), Princess Elisabeth of the Palatinate, or Princess-Abbess of Herford Abbey, was the eldest daughter of Frederick V, Elector Palatine (who was briefly King of Bohemia), and Elizabeth Stuart. Elisabeth of the Palatinate was a philosopher best known for her correspondence with René Descartes. She was critical of Descartes' dualistic metaphysics and her work anticipated the metaphysical concerns of later philosophers.

Prince Rupert of the Rhine, Duke of Cumberland, KG, PC, FRS (17 December [O.S. 27 December] 1619 – 29 November [O.S. 9 December] 1682) was an English–German army officer, admiral, scientist, and colonial governor. He first rose to prominence as a Royalist cavalry commander during the English Civil War. Rupert was the third son of the German Prince Frederick V of the Palatinate and Elizabeth, eldest daughter of King James VI and I of Scotland and England respectively.

Prince Rupert had a varied career. He was a teenage soldier fighting alongside Dutch forces against Habsburg Spain during the Eighty Years' War (1568–1648), and against the Holy Roman Emperor in Germany during the Thirty Years' War (1618–1648). Aged 23, he was appointed commander of the Royalist cavalry during the English Civil War, becoming the archetypal "Cavalier" of the war and ultimately the senior Royalist general. He surrendered after the fall of Bristol and was banished from England. He served under King Louis XIV of France against Spain, and then as a Royalist privateer in the Caribbean Sea. Following the Restoration, Rupert returned to England, becoming a senior English naval commander during the Second Anglo-Dutch War and Third Anglo-Dutch War, and serving as the first governor of the Hudson's Bay Company. He died in England in 1682, aged 62.

Robert Wintour (1568 – 30 January 1606) and Thomas Wintour (1571 or 1572 – 31 January 1606), also spelt Winter, were members of the Gunpowder Plot, a failed conspiracy to assassinate King James I. They were brothers, and related to other conspirators, such as their cousin, Robert Catesby; a half-brother, John Wintour, also joined them following the plot's failure. Thomas was an intelligent and educated man, fluent in several languages and trained as a lawyer, but chose instead to become a soldier, fighting for England in the Low Countries, France, and possibly in Central Europe. By 1600, however, he changed his mind and became a fervent Catholic. On several occasions he travelled to the continent and entreated Spain on behalf of England's oppressed Catholics, and suggested that with Spanish support a Catholic rebellion was likely.

As momentum was building behind a peace settlement between the two countries, Thomas's pleas were ignored. Instead, in 1604 he decided to join with Catesby, who planned to restore England to Catholicism by killing the king and inciting a popular revolt in the Midlands, during which James's daughter, Princess Elizabeth, would be installed as titular queen. Thomas returned to the continent and again failed to elicit Spanish support, but instead met Guy Fawkes, with whom he returned to England. Robert, a devout Catholic who inherited Huddington Court near Worcester, joined the conspiracy the following year.

John Grant (c. 1570 – 30 January 1606) was a member of the failed Gunpowder Plot, a conspiracy to replace the Protestant King James I of England with a Catholic monarch. Grant was born around 1570, and lived at Norbrook in Warwickshire. He married the sister of another plotter, Thomas Wintour. Grant was enlisted by Robert Catesby, a religious zealot who had grown so impatient with James's lack of toleration for Catholics that he planned to kill him, by blowing up the House of Lords with gunpowder. Grant's role in the conspiracy was to provide supplies for a planned Midlands uprising, during which James's daughter, Princess Elizabeth, would be captured. However, on the eve of the planned explosion, Guy Fawkes was discovered guarding the explosives the plotters had positioned in the undercroft beneath the House of Lords, and arrested.

As the government searched for Fawkes's accomplices, Grant and the others engaged in a futile mission for support for the uprising. They stole horses from Warwick Castle, and further supplies from Hewell Grange, before stopping at Holbeche House. The plotters laid in front of the fire some of the gunpowder they had collected, to dry out, but a stray spark ignited the powder, and in the resultant conflagration Grant was blinded. Government forces besieged the house, and he was captured and taken to London.

Ambrose Rookwood (c. 1578 – 31 January 1606) was a member of the failed 1605 Gunpowder Plot, a conspiracy to replace the Protestant King James I with a Catholic sovereign. Rookwood was born into a wealthy family of Catholic recusants, and educated by Jesuits in Flanders. His older brother became a Franciscan, and his two younger brothers were ordained as Catholic priests. Rookwood became a horse-breeder. He married the Catholic Elizabeth Tyrwhitt, and had at least two sons.

He was enlisted into the plot in September 1605 by Robert Catesby, a religious zealot whose impatience with James' treatment of English Catholics had grown so severe that he conspired to blow up the House of Lords with gunpowder, killing the king and much of the Protestant hierarchy. With the other conspirators he had recruited, Catesby also planned to incite a rebellion in the Midlands, during which James's nine-year-old daughter Princess Elizabeth would be captured, and installed as titular queen. Rookwood's stable of fine horses was essential for the uprising to succeed.