History

Some believe that Hannah Montague invented this collar in Troy, New York, in 1827, after she snipped off the collar from one of her husband's shirts to wash it, and then sewed it back on. The Rev. Ebenezar Brown, a businessman in town, proceeded to commercialize it. The manufacture of detachable collars and the associated shirts became a significant industry in Troy.

Wider Scope

It was later that the benefit of being able to  starch the collars became apparent, and for a short time, various other parts of the shirt, such as the front and cuffs, were also made detachable and treated to rigid stiffness. As more emphasis started to be placed on comfort in clothing this practice declined, and the stiff collar is the last surviving use of such heavily starched cotton in daywear; while a full dress shirt  (worn with white tie and occasionally black tie) still has a stiff, but attached, front and cuffs to accompany the stiff detachable collar.

Studs

The collar is attached to the shirt by a pair of studs like those shown. The shirt has a tunic collar, a short upright band of fabric with a hole at the back and one on each side at the front. The stiff collar is attached at the back before the shirt is donned (and the tie placed under the collar for a turndown collar), then the shirt is put on, after which the front stud is pushed through the collar to fasten it.