The future king and prince of Asturias, Charles IV, had been married for five years with no offspring, reason for which when his first child was born his grandfather, Charles III, wanted to leave evidence of his gratitude to God — to whom he declared having prayed to while waiting for the continuation of the dynasty — and, specifically, to the Virgin Mary in his advocacy of the Immaculate Conception and of whom he declared himself the profoundly devout king.

Although the child and various brothers died soon after, Charles III maintained his agreement, and the number of Crosses given was greatly reduced at the monarch's regret.

The insignias of the Order have varied throughout time, but have invariably maintained some original features: blue silk band with white design, an eight-point cross with the image of the Immaculate Conception, the motto Virtuti et Merito and the figure of Charles III.

At this moment the duties and requirements of the titles were specified: they needed to have "pure and noble blood" up to their great-grandparents, as was regulated by the Castilian Fueros and the other valid laws.

The king was especially careful to incorporate into the Order theologians of the Crown that investigated the mysteries of the Virgin Mary, in some cases the clergymen being greater in number than the knights and nobles of which it was made up.

The Peninsular War caused two institutions to attribute the faculty of the government of the Order: Joseph Bonaparte and the Suprime Central Junta.

The colours of the band of the Order were adopted by some members of the Provisional Government of Argentina to signify their adhesion to King Ferdinand VII and would later come to represent the movement for independence.

[2] The regulation sets the objective of the order as a means of "rewarding the citizens who, with their effort, initiative and work, have brought a distinguished and extraordinary service to the Nation".