The following article is taken from my book,

Blue Smoke Risin' on the Mountain --

a beginner's guide to the mountain dulcimer, 2d edition

copyright 2008 Lee Cagle

The mountain dulcimer is a beautiful instrument, both visually and in its sound. Although its roots lie in the Appalachian Mountain region of the United States, it has captured the fascination of musicians across the globe.
When the United States began to be settled by Europeans, the adventurers and pioneers brought their musical instruments with them from across the ocean. Can you imagine how important music must have been to these people for them to bring their instruments on the long, grueling ocean voyage, where space and possessions were very limited?

When bringing the instrument was not possible, they brought the memory of their European instruments and built instruments after arriving in the New World, using native woods and materials.

These courageous and musically stubborn forebearers brought fiddles, guitars, pianofortes, lutes, horn, accordians. And for all of the American ingenuity to which we lay claim, there are few instruments that we can claim as our own.

Based on African gourd instruments, African-Americans gave us the banjo which was used in the minstrel shows of the 1800s. That gift has become the backbone of bluegrass music and the Dixieland sound.

In an effort to reach the masses, the autoharp was produced and sold through the Sears & Roebuck catalogue. This instrument allowed even the most inexperienced player to join in by pressing buttons to make chords while strumming across the strings.

And the mountain dulcimer! No one knows the person who managed to develop the dulcimer in its current form.  The mountain dulcimer combines features similar to the fretted zither, the German scheitholt, the Norwegian langeleik  and Swedish hummel into the instrument that we play and love today. I am daily amazed at the thought and foresight in the design of this instrument.

The dulcimer has been known by many names including Appalachian dulcimer, lap dulcimer, mountain dulcimer, dulcimore, dulcymore, harmony, harmonium, and hog fiddle. The word
    SCHEITHOLTS                       "dulcimer" comes from the Latin "dulce" which means sweet and the Greek "melos" which means
                                              music. Some also theorize that people were not allowed to be associated with instruments that
                                              were not mentioned in the Bible, so it was a way to have their music without angering the local
                                              preacher. (Remember, the fiddle was called the Devil’s box because it was considered a sin
                                              to play.)1

Traditionally, the mountain dulcimer was played only on the melody string. Therefore, the frets were partial frets placed under the melody string only and did not extend across the fretboard as they do today. The player many times used a wooden stick called a "noter" to fret. Also, prior to the widespread use of plastic picks, the dulcimer was often strummed with a turkey or goose feather. The bass and middle strings were not fretted. They were tuned to harmony notes and acted as drones behind the melody.

There have been many updates in the design of the dulcimer over the years. Shapes have changed from boxes to hourglass and teardrop shapes. Picks have replaced feathers. Frets now extend across the fretboard. Fingers have replaced wooden noters, and chording, rather than melody only, has become commonplace. Also, early dulcimers did not have a 6 ½ fret which was not added until the 1970s. The addition of this fret allows today’s players to play two different scales — the Ionian
          HUMMEL                        scale and the Mixolydian scale — without re-tuning.