Tanto monta, monta tanto, Isabel como Fernando

Tanto monta, monta tanto, Isabel como Fernando (pronounced: [ˈtanto ˈmonta, ˈmonta ˈtanto, isaˈβel ˈkomo ferˈnando]; "They amount to the same", or "Equal opposites in balance") was the alleged motto of a prenuptial agreement made by the Spanish Catholic Monarchs, Isabella I of Castile and Ferdinand II of Aragon. During their joint reign they did in fact support each other effectively in accordance with their motto of equality. Still, the wording "Tanto monta, monta tanto, Isabel como Fernando" is actually a popular saying invented many centuries later, not the real motto. Besides, and contrary to popular belief, it was only the motto of King Ferdinand of Aragon, and never used by Isabella. Both the full version of the slogan and the unsourced idea that it referred to the two monarchs was a Romantic myth, aimed at fostering the idea that Isabella and Ferdinand ruled over a unified monarchy. In truth, both realms remained separate during their lives.

The Catholic Monarchs' great sword kept in the Real Armería in Madrid, made in the 15th century, was used during the reign of Ferdinand II of Aragon and Isabelle of Castile and in all solemn court occasions until the 18th century. With this sword, the Catholic Monarchs Ferdinand and Isabella knighted Christopher Columbus on his return from his first voyage to America. In the Throne Hall of the Royal Palace in Barcelona, Columbus was named "Admiral of the Ocean" and "Viceroy of the Indies". This ceremonial sword was used as the symbol of the royal power in all religious and political ceremonies starting with the conquest of Granada and the beginning of Spain as a nation. On its hand guard it bears the inscription "Tanto monta, monta tanto" that translates roughly to "As much as the one is worth, so too is the other."

Another version holds that the motto comes from the proverb Tanto monta cortar como desatar ("It amounts to the same, cutting as untying"), from the Classical story of the Gordian knot where Alexander the Great, wanting to untie the knot of a sacred yoke at Gordion to fulfill the prophecy of the conquest of Asia, decided to cut it with his sword. Hence it is associated to the yoke in the emblem of the yoke and arrows.

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