At the time of conquest
It is a well-known fact that the European nations competed against each other for the conquest of the New World. All were after gold, to fund the war against Islam raging in the south of Europe. The Spaniards didn't find gold but went on to explore the land and sent many missionaries there.
It was in this historical context that King Philip IV of Spain made his order by edict dated May 10, 1643:
"In gratitude for the great mercy and the favors received from the Blessed Virgin Mary, we place our whole kingdom of America under her protection and order that each year, in every town and village, a novena be organized, with a solemn Mass and the presence of the officials of the crown; and that statues of the Blessed Virgin be carried in procession. We ask our bishops to exhort the Christian people to piety and devotion toward Mary, Our Lady, patroness and sovereign."
After Protestantism settled in
Later, when the English and the Dutch arrived, the colonies formed the federation of the United States and the great nation became almost entirely Protestant. Fortunately, thanks to their need to secure the French as allies, freedom of religion was maintained and the Catholics, concentrated mainly in Maryland, formed their first diocese in 1789. The name Maryland recalls the fact that the Virgin Mary was invoked in this state as Helper of the Afflicted by the English and Irish Catholics, who were denigrated by the Protestants in the middle of the 17th century.
In 1846, the American bishops gathered in provincial council in Baltimore and entrusted the United States to The Immaculate Conception of Mary.
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