History of guitars.

Before the development of the electric guitar and the use of synthetic materials, a guitar was defined as being an instrument having "a long, fretted neck, flat wooden soundboard, ribs, and a flat back, most often with incurved sides". The term is used to refer to a number of related instruments that were developed and used across Europe beginning in the 12th century and, later, in the Americas. These instruments are descended from ones that existed in ancient central Asia and India. For this reason guitars are distantly related to modern instruments from these regions, including the tanbur, the setar, and the sitar. The oldest known iconographic representation of an instrument displaying the essential features of a guitar is a 3,300 year old stone carving of a Hittite bard.

The modern word guitar, and its antecedents, have been applied to a wide variety of cordophones since ancient times and as such is the cause of confusion. The English word guitar, the German gitarre, and the French guitare were adopted from the Spanish guitarra, which comes from the Andalusian Arabic qitara, itself derived from the Latin cithara, which in turn came from the Ancient Greek kithara, and is thought to ultimately trace back to the Old Persian language. Tar means string in Persian.

Although the word guitar is descended from the Latin word cithara, the modern guitar itself is not generally believed to have descended from the Roman instrument. Many influences are cited as antecedents to the modern guitar. One commonly cited influence is of the arrival of the four-string oud, which was introduced by the invading Moors in the 8th century. Another suggested influence is the six-string Scandinavian lut (lute), which gained in popularity in areas of Viking incursions across medieval Europe. Often depicted in carvings c. 800 AD, the Norse hero Gunther, played a lute with his toes as he lay dying in a snake-pit, in the legend of Siegfried. It is likely that a combination of influences led to the creation of the guitar; plucked instruments from across the Mediterranean and Europe were well known in Iberia since antiquity

Two medieval instruments that were called "guitars" were in use by 1200: the guitarra morisca (Moorish guitar) and the guitarra latina (Latin guitar). The guitarra morisca had a rounded back, wide fingerboard, and several soundholes. The guitarra Latina had a single soundhole and a narrower neck.
http://en.wikipedia.org/wiki/Guitar

The Guitarra Latina was very similar in shape to the classical guitar of today. It was equipped with 8 strings doubled up as pairs, and had one single sound hole. It is thought to have come to Spain from other parts of Europe. http://fretspider.com/history/acoustic/