St. Valentine's Day
Symbols Found on Valentines

There have been valentines from the beginning of time yet, oddly enough, the man who originally offered himself as a valentine had nothing so romantic in mind.  St. Valentine was a young Roman who was martyred for refusing to give up Christianity.  He died in A.D.270 on February 14, the very day that, by coincidence, had been devoted to love lotteries and to fine-feathered friendship.  According to legend, he left a farewell note for the jailer's little daughter, who had befriended him in prison, and signed it "from your Valentine".
Many signs and symbols connected with Valentine's Day are ancient indeed.  The red heart, like the red rose, which often crops up on valentine cards, has signified love and emotion since early Roman times.

Ribbons, Laces and Frills

Ribbons and frills have been associated with romance since the days of knighthood, when the chap in shiny armor rode into battle with a ribbon or scarf given him by his lady fair.  According to the dictionary, the word "lace" comes from a Latin word meaning to "snare" or "noose", so its appropriate to a valentine.

Cupid
Cupid was one of the gods of mythology, whose name in Latin means "desire".  He is usually represented as a chubby, naked, winged boy or youth with a mischievous smile.  He possessed a bow with a quiver of arrows by which he transfixed the hearts of youths and maidens.  His darts, so of which were poisonous at the tip, could pierce anywhere. 
Cherubs are descendants of Cupid.  They are lovable little winged creatures, generally without arrows and quiver.  They may be mischievous, but not like Cupid, who aims and draws regardless of the consequences.

The Rose
The rose, which speaks of love, is undoubtedly the most popular flower in the world.  By rearranging the letters in the word "rose", we get "Eros" the god of Love.  This may explain why it has always been called the flower of romance, the choice of lovers in every century.

Violets
There is a legend about the imprisoned young Christian named Valentine.  During his confinement, often and longingly he thought of his loved ones and wanted to assure them of his well being.  Beyond his window, within his reach, grew some violets.  He picked some of the leaves and pierced them with the words "Remember your Valentine" and sent them off by a dove.  On the following day he sent more messanges which simply said "I love you".
The story of the valentine in America appears to have begun during the middle of the 18th century.  Valentines were laboriously wrought and most were void of lacy frills, undoubtedly for lack of materials.  Instead, they displayed fine workmanship in pen and ink, cut paper, and hand-painted designs of flowers, hearts, birds, etc., in elaborate colors. 

XXX for Kisses
Lovers who affectionally sign "XXX"s to valentine cards and letter are usually unaware that the custom goes back to the early Christian era, when a cross mark, or "X", conveyed the force of a sworn oath.  The cross was, of course, a religious symbol.  Not only did it refer to the cross of Calvary; it also was the first letter of the Greek word for Christ, Xristos.  In the days when few people could write, their signature cross, or "X", was a legally valid mark.  To emphasize their complete sincerity in an accord, they often kissed the mark, as a Bible was frequently kissed when an oath was sworn upon it.  It was this practice of kissing the "X" that led to its becoming a symbol of a kiss.  During WW II, the British and American governments both forbade men in the armed forces from putting "XXX"s on their letters, afraid that spies within the services might begin sending clandestine messages coded as kisses.
(Source: (1) The Book of Festival Holidays by Marguerite Ickis; (2) Extraordinary Origins of Everyday Things by Charles Panati)