Charles IV (Czech: Karel IV., German: Karl IV., Latin: Carolus IV; 14 May 1316 – 29 November 1378), born Wenceslaus, was the first King of Bohemia to become Holy Roman Emperor.
His mother, Elizabeth of Bohemia, was the sister of King Wenceslas III, the last of the male Premyslid rulers of Bohemia.
Charles inherited the County of Luxembourg from his father and was elected king of the Kingdom of Bohemia.
On 2 September 1347, Charles was crowned King of Bohemia.
On 11 July 1346, the prince-electors chose him as King of the Romans (rex Romanorum) in opposition to Emperor Louis IV.
Charles was crowned on 26 November 1346 in Bonn.
After his opponent died, he was re-elected in 1349 and crowned King of the Romans.
In 1355, he was crowned King of Italy and Holy Roman Emperor.
With his coronation as King of Burgundy in 1365, he became the personal ruler of all the kingdoms of the Holy Roman Empire.