Final answer:
The fleur-de-lis represents French Royalty and the Holy Trinity, serving both as a symbol of divine right to rule and a religious emblem, frequently depicted in art associated with King Louis IX and his mother, Blanche of Castile.
Step-by-step explanation:
The flower that represents French Royalty and the Holy Trinity is the fleur-de-lis, a symbol that has long been associated with the monarchs of France. This stylized iris or lily has connotations of religious, political, and dynastic rights to rule. During the medieval period, the fleur-de-lis was prominently featured in art and artifacts to denote the divine right and status of the French kings.
King Louis IX, also known as Saint Louis, was frequently depicted with the fleur-de-lis to indicate his royal lineage and his role as a leader anointed by God. The fleur-de-lis is also present in the sumptuous reliquary that holds a single thorn from the crown of thorns bought by King Louis IX, highlighting the significance and reverence of the symbol within the French monarchy.
In Gothic art, which Blanche of Castile, the mother of King Louis IX, was a major patron of, the fleur-de-lis was recurrently used to connect the earthly realm of royal power with the divine, drawing parallels between the monarchy and the blessed figures of the Vir_gin Mary and Christ in Christian iconography.