When we see a snowy white or colorful handkerchief it does not strike us that this piece of material might have a history. And yet this small object has a longer history than many other fashion accessories.
The first known mention is by Catullus (87-57 BC) who speaks about them in his poems as if they were in general use. However, he gives no information on their frequency or their previous use.
Handkerchiefs have performed a variety of functions throughout history, and included cloths that were used for absorbing perspiration, for veiling one's face, and frequently for covering the mouth for protection against adverse weather conditions or infectious diseases.
During the first century BC, these cloths were used almost exclusively by members of the highest social and ruling class as a fashionable luxury. This was the result of linen, the fabric of choice, being very expensive.
Only after imports of flax had increased and following the growing demands of the middle classes and simpler people, were handkerchiefs used more generally in the centuries following the birth of Christ. These cloths were kept in the fold of the garment on the chest. As neither the masculine toga, nor the women's garments had pockets as we know them today.
In approximately 300 AD, we find our first reference to a cloth which served only for cleaning one's nose. However, during the same period it became customary to wave handkerchiefs to greet the appearance of high ranking persons in the theater or to express applause.
Throughout the middle ages, we find only rare references to these cloths. But, at the start of the 14th century we begin to see more frequent references. Although, we initially see it only in those countries in Europe where a pronounced courtly culture had fostered the feeling for richly decorated cloths, especially in Italy and France.
In the course of the 16th century, the decorative handkerchief gained increasing importance in European society and came to be even more richly and magnificently decorated. The knotted fringes of the seams, the simple edge picots, and the small scallops made way for dainty, fancy designs in sewn lace and pillow lace. Therefore, it became a display and fashion object of the greatest importance.
An entirely new task was in store for the handkerchief when tobacco made its triumphant entry into Europe during the 16th century. However, in the 17th century, tobacco was rarely smoked, as the taking of snuff was considered to be more elegant. But, what could be done with the eternally brown little noses of the beautiful ladies, which did not match their elegant clothes at all? For this, only a handkerchief could help, but the small square decorated with lace was entirely unsuitable. Those who wanted to take snuff had to use large colored squares on which the brown tobacco stains were less visible.
In the 18th century, the handkerchief found public use in the theater, where it became the prerequisite in tragedies in France and eventually throughout Europe.
It was during the 19th century that ladies regarded the handkerchief as an indispensable accessory for an elegant costume. It no longer disappeared in the bags that they carried because they were artistically decorated articles which had to be properly appreciated. There, most ladies carried them openly in the hands, even in the streets. Handkerchiefs became so commonplace and were used so universally that everyone carried a hankie whenever they went out.
This custom made it easy for young people - even though carefully chaperoned - to work out a system of signals that enables them to carry on a conversation across the room. For instance, if a young lady drew the hankie across her lips, while looking at a young man, it meant that she was desirous of making his acquaintance. If she already knew the young man, signals could get personal, such as:

Drawing a hankie across her cheek meant
"I love you!"
A hankie held to the right cheek meant
"yes."
Yet if it was held on the left cheek it meant
"no."
A hankie drawn across the forehead signaled
"we are being watched."
And, if thrown over the shoulder, the message
was "follow me."

Handkerchiefs continued to diversify. Some were made completely out of lace, others embroidered and edged in lace, and many were made with simple tatted borders. Handkerchiefs were considered the perfect gift for everyone including mere acquaintances. As a result, hankies were made and exchanged by the thousands.