Answer:

Habsburg Empire of Charles V

Explanation:

The dominions of Charles V in Europe and the Americas were the first collection of realms to be referred to as the "empire on which the sun never sets".

Answer:

The phrase "the empire on which the sun never sets" (Spanish: el imperio donde nunca se pone el sol) has been used to describe certain global empires that were so extensive that it seemed that at least one part of their territory was always in daylight. This statement is typically a hyperbolic boast of an empire's reach, but it has also been interpreted in a literal sense.[1][2][3]

Flag of the Spanish Empire

It was originally used for the universal monarchy of the European and American dominions under Emperor Charles V.[4][5][6] The term was then used for the Spanish Empire of Philip II of Spain and successors, in the 16th, 17th and 18th centuries.[7][8] In more recent times, it was used for the British Empire, mainly in the 19th and early 20th centuries, a period in which the British Empire reached a territorial size larger than that of any other empire in history. In the 20th century, the phrase has sometimes been adapted to refer to the global reach of American power.