- Gustavus, Gustavus II, Gustavus Adolphus - king of Sweden whose victories in battle made Sweden a European power; his domestic reforms made Sweden a modern state; in 1630 he intervened on the Protestant side of the Thirty Years' War and was killed in the battle of Lutzen (1594-1632)
--1 is a kind of king, male monarch
- Gustavus, Gustavus I - king of Sweden who established Lutheranism as the state religion (1496-1560)
--2 is a kind of king, male monarch