The United Kingdom of Scandinavia was formed on May 17th 1507 under its first king, Erik III "The Unifier." Prior to unification, there were the separate kingdoms of Sweden, Norway, Denmark, Helsinki (Finland), Turku (Finland), and the Saami (Finland). The title of heir apparents is "HRM The Prince(ss) of Finland" To date Scandinavia practices male primogeniture (like other European countries). This means that if the Scandinavian Royals have a first-born that is a girl, she will lose her title as Princess of Finland to her younger brother- becoming the Prince of Finland.
The formal title of the King is: His Royal Majesty, King (Queen) of Sweden, Norway, Denmark,Finland, and Portugal; The Grand Scandinavian, Duke(Duchess) of Schleswig-Holstein, Protector (Protectress) of the Saami, Preserver of the Perpetual Union of the Scandinavian Kingdoms; Preserver of Portugal and the Algarves.
1. King Erik III "The Unifier"(1503-1547) Spouse: Her Royal Majesty Queen Christina of Scandinavia (married 1502)
Heir apparent: Erik IV, Prince of Finland (b.1504)
Actual Successor (may vary from the Heir apparent for multiple reasons): Victoria, Princess of Sweden
Erik IV, Prince of Finland (1504-1541) -- married to Theresa of Brandenburg (1519).
Victoria, Princess of Sweden (1505-1541) -- married to Pedro, Crown Prince of Portugal (1520)
Haakon, Prince of Norway (1512-1541) -- married to Princess of Anhalt (1531)
Christian, Prince of Denmark (1513-1541) -- married to Princess of Muscovy
Margrethe, Duchess of Oslo (b.1521)
Aleksander, Duke of Stockholm (b. 1530)
2. Queen Victoria (1547-1564)
Spouse: His Royal Majesty the Prince Regent Pedro II of Portugal (married 1520)
Heir apparent: Denis, Prince of Finland
Actual successor: Alfonse, Prince of Finland (acquired title after his brother's death in 1562)
Urraca, Princess of Sweden (1523-1586)
Denis, Prince of Finland (1525-1562)
Alfonse, Prince of Finland (1527-1580)
3. King Alfonse (1564-)
Spouse: HRM Queen Selena of Bavaria
Heir apparent: João IV of Portugal
Actual successor: ???
- João IV of Portugal (1555-1583)
- Garcia I of Portugal (1557-1622)
- Karina (1559-)
- Leonor (1563-)