As he grew to manhood, he lost the gaucherie of his earlier years, and it soon became apparent that, even if he was lacking in good looks, he had a natural charm and magnetism which were acknowledged by friends and enemies alike.
As a man, too he threw off the early aversion to academic work, and over the years he became the hardest-working monarch of his time and perhaps one of the hardest-working sovereigns of any time was conscientious almost to a fault, and determined to make omission of his childhood. When he first arrived in Spain at the age of seventeen, his subjects there were horrified to find that could not speak a word of Spanish; but they were no more dismayed than Charles, who about learning the language, and succeeded so well that it became his native tongue.
Indeed, it has been said that Charles `was born in French and died in Spanish’. In addition, he spoke Flemish, German, and enough Italian and Latin to understand ambassadors when they addressed him in those languages, and there may be some truth in the celebrate story that he once said that French was the language he spoke diplomats, Italian to women, German to stable-boys, and Spanish to God.
At the time of his birth, a Neapolitan astrologer, Lorenzo Miniate, predicted that Charles would become the greatest captain of his age. Claims to overall supremacy in any are always difficult to substantiate but if he did not become the greatest military ambition was to win battles with the least possible loss of life: an ambition for which courage and for his willingness to share the hardships and dangers of the battlefield with them.