Buy this book on Amazon: A Short History of the World
By the time Charles became Holy Roman Emperor in 1519, his Habsburg family, through a number of successful marriages, owned the largest western empire since Roman times including Spain, the Netherlands, Austria and a number of smaller countries, not to mention Spain’s rich, though unexplored, colonies in the Americas. His empire encompassed so many cultures and languages that he was said to have spoken Spanish to God, French to his mistress, and German to his horse. King of Spain already since 1516, he began to regard the country as the most important part of his empire, leaving the German-speaking provinces to be governed by his brother, Ferdinand.
Emperor for 39 years in a hugely important period for Europe, Charles V spent his reign fighting against the French over lands in Italy and the Netherlands,68 against a defensive league of Protestant princes in Germany, against the Ottoman Turks in the Mediterranean, and even against the Pope, sacking Rome in 1527 and driving the Pope into exile because the Vatican had allied itself with the French. Overseas, Charles oversaw the Spanish colonisation of the Americas, including the conquest of both the Aztec and Inca empires.