Europe

Illustration of a Celtic Druid playing the harp

While the angle and bow harps held popularity elsewhere, European harps favored the "pillar", a third structural member to support the far ends of the arch and sound box. A harp with a triangular three-part frame is depicted on 8th-century Pictish stones in Scotland and in manuscripts (e.g. the Utrecht Psalter) from the early 9th-century France. The curve of the harp's neck is a result of the proportional shortening of the basic triangular form to keep the strings equidistant; if the strings were proportionately distanced, the strings would be farther apart.

A medieval European harp (the Wartburg harp) with buzzing bray pins.

As European harps evolved to play more complex music, a key consideration was some way to facilitate the quick changing of a string's pitch to be able to play more chromatic notes. By the Baroque period, in Italy and Spain, more strings were added to allow for chromatic notes in more complex harps. In Germany in the second half of the 17th century, diatonic single-row harps were fitted with manually turned hooks which fretted individual strings to raise their pitch by a half step. In the 18th century, a link mechanism was developed connecting these hooks with pedals, leading to the invention of the single-action pedal harp.

The first primitive form of pedal harps was developed in the Tyrol region of Austria. Jacob Hochbrucker was the next to design an improved pedal mechanism, around 1720, followed in succession by Krumpholtz, Nadermann, and the Erard company, who came up with the double mechanism, in which a second row of hooks was installed along the neck, capable of raising the pitch of a string by either one or two half steps. While one course of European harps led to greater complexity, resulting largely in the modern pedal harp, other harping traditions maintained simpler diatonic instruments which survived and evolved into modern traditions.

Americas

In the Americas, harps are widely but sparsely distributed, except in certain regions where the harp traditions are very strong. Such important centres include Mexico, the Andean region, Venezuela and Paraguay. They are derived from the Baroque harps that were brought from Spain during the colonial period. Detailed features vary from place to place.

The Paraguayan harp is that country's national instrument, and has gained a worldwide reputation, with international influences alongside folk traditions. Paraguayan harps have around 36 strings, played with the fingernails, and with a narrowing spacing and lower tension than modern Western harps, and have a wide and deep soundbox which tapers to the top.

The harp is also found in Argentina, though in Uruguay it was largely displaced in religious music by the organ by the end of the 18th century. The harp is historically found in Brazil, but mostly in the south of the country.

Mexican "jarocha" harp music of Veracruz has also gained some international recognition, evident in the popularity of "la bamba".[ In southern Mexico (Chiapas), there is a very different indigenous style of harp music.

In Venezuela, there are two distinct traditions, the arpallanera and the arpa central (or arpamirandina). The modern Venezuelan arpallanera has 32 strings of nylon (originally, gut). The arpa central is strung with wire in the higher register. In Perú harp is used commonly in the Andean music genre of huayno.

Africa

A Mangbetu man playing a bow harp.

A number of types of harps are found in Africa, predominantly not of the three-sided frame-harp type found in Europe. A number of these, referred to generically as African harps, are bow or angle harps, which lack forepillars joining the neck to the body.

A number of harp-like instruments in Africa are not easily classified with European categories. Instruments like the West African kora and Mauritanian ardin are sometimes labeled as "spike harp", "bridge harp", or "harp lute" since their construction includes a bridge which holds the strings laterally, vice vertically entering the soundboard.

South and Southwest Asia

While lyres and zithers have persisted in the Middle East, most of the true harps of the region have become extinct, though some are undergoing initial revivals. The Turkish çeng was a nine-string harp in the Ottoman Empire which became extinct at the end of the 17th century, but has undergone some revival and evolution since the late 20th century. A similar harp, the changi survives in the Svaneti region of Georgia. 
In the remote and mountainous Nuristan province of Afghanistan the Kafir harp has been part of the musical traditional for many years. In India, the bin-baia harp survives about the Padhar people of Madhya Pradesh.

East Asia

Saung musician in 1900.

The harp largely became extinct in East Asia by the 17th century; around 1000 CE harps like the vajra began to replace precedingharps. A few examples survived to the modern era, particularly Burma's saung-gauk, which is considered the national instrument in that country. Though the ancient Chinese konghou has not been directly resurrected, the name has been revived and applied to a modern newly invented instrument based on the Western classical harp, but with the strings doubled back to form two notes per string, allowing advanced techniques such as note-bending.

Modern European and American harps

Concert harp

Main article: Pedal harp

Double action pedal harp

The pedal or concert harp is a technologically advanced instrument, particularly distinguished by its use of "pedals", foot-controlled devices which can alter the pitch of given strings, making the instrument fully chromatic and thus able to play a wide body of classical repertoire. Pedals were first introduced in 1697 by JakobHochbrucker of Bavaria. In 1811 these were upgraded to the "double action" pedal system patented by SébastienErard.

The addition of pedals broadened the harp's abilities, allowing its gradual entry into the classical orchestra, largely beginning in the 19th century. Though the harp played little or no role in early classical music (being used only a handful of times by such as Mozart or Beethoven), and its usage by Cesar Franck in his Symphony in D minor (1888) was described as "revolutionary" despite some body of prior classical usage. Entering the 20th century, the pedal harp found use outside of classical music, entering jazz with Casper Reardon, the Beatles 1967 "She's Leaving Home", and several works by Björk which featured harpist ZeenaParkins.