There’s been an unbroken sequence of descent since William the Conqueror, but sometimes they’ve had to “go shopping” to find the next person in line. The Hanover thing (which predates Victoria by about 100 years) is the biggest such case. Sequence is as follows:
[ul][li]William I (conquered England 1066)[/li][li]William II, second son of William I, died childless[/li][li]Henry I, third son of William I[/li][li]Stephen, son of William I’s daughter Adela[/li][li]Henry II, son of Henry I’s daughter Matilda[/li][li]Richard I, second (eldest surviving) son of Henry II, died childless[/li][li]John, fourth (and eldest surviving) son of Henry II[/li][li]Henry III, son of John[/li][li]Edward I, son of Henry III[/li][li]Edward II, son of Edward I[/li][li]Edward III, son of Edward II[/li][li]Richard II, son of Edward III’s son Edward (the Black Prince), who died the year before his father[/li][li]Henry IV, son of Edward III’s third son John of Gaunt[/li][li]Henry V, son of Henry IV[/li][li]Henry VI, son of Henry V[/li][li]Edward IV, lineal descendent of Edward III on both sides – his mother was the daughter of the Earl of March whose mother was the daughter of Edward III’s second son, and his father (Richard Duke of York) was the son of the son of Edward III’s fourth son[/li][li]Edward V, son of Edward IV, died childless[/li][li]Richard III, third son of Richard Duke of York[/li][li]Henry VII, son of the only daughter of the eldest son of John of Gaunt’s third marriage[/li][li]Henry VIII, son of Henry VII[/li][li]Edward VI, son of Henry VIII, died childless[/li][li]Mary I, daughter of Henry VIII, died childless[/li][li]Elizabeth I, daughter of Henry VIII, died childless[/li][li]James I of England and VI of Scotland, son of James V of Scotland and Margaret, daughter of Henry VII[/li][li]Charles I, son of James I[/li][li]Charles II, son of Charles I, died without legitimate children[/li][li]James II of England and VII of Scotland, second son of Charles I. When he attempted to return the country to Catholicism, he was forced into exile.[/li][li]Mary II, daughter of James II, and her husband and co-ruler [/li][li]William III, son of a daughter of James I[/li][li]Anne, daughter of James II, whose children all predeceased her. During her reign England and Scotland were joined into one kingdom, Great Britain, and an Act of Succession passed that required the throne go to a Protestant next in the line of succession, bypassing a number of Catholics, including Mary and Anne’s brother[/li][li]George I, son of the daughter of a daughter of James I[/li][li]George II, son of George I[/li][li]George III, son of George II’s son Frederick, Prince of Wales[/li][li]George IV, eldest son of George III, died without legitimate surviving children[/li][li]William IV, eldest surviving son of George IV, died without legitimate surviving children[/li][li]Victoria, daughter of George III’s son the Duke of Kent, who had died some years before[/li][li]Edward VII, son of Victoria[/li][li]George V, son of Edward VII[/li][li]Edward VIII, eldest son of George V, abdicated in order to marry contrary to the laws of the church at the time[/li][li]George VI, second son of George V[/li][li]Elizabeth II, elder daughter of George VI[/ul][/li]
It’s interesting to note that Prince Philip, Duke of Edinburgh, is in the line of succession in his own right as a descendent of Queen Victoria, though he’s well past the 100th-in-line mark of yabob’s list.
Regarding the Swedish royalty, Marshall of France Jean-Baptiste Jules Bernadotte was adopted by King Karl XIII, there being no legitimate sane heir to the Vasa royal house to succeed him, and became King Karl XIV Johan on Karl XIII’s death. The present royal house is descended from him. Bernadotte was born of petit bourgeois stock in Pau, in extreme southern France near the Spanish border, and rose under Napoleon to an army command.