After an earthquake devastated the small Italian town of Salle in 1905, two brothers-in-law, Rocco and Carmine D'Addario emigrated to Astoria in Queens, New York in an attempt to expand their market, importing and selling the strings made by their family in Salle. In 1918, Carmine (who later became known as Charles) began making his own ropes and strings in a small shop behind the family home. Still crafting with animal gut, the process of making strings involved all members of the family.
The guitar saw a major rise in popularity in the early part of the 20th century, because of new popular music, and sometime in the 1930s the D’Addario family began making strings for the guitar, producing them in a made-to-order fashion for individual musicians and guitar manufacturers.
The development of nylon by DuPont during World War II produced a major change in the family business. Sent samples by Dupont in 1947, the D'Addario family immediately began experimenting with this new material, consulting with many of its regular customers in developing nylon strings for classical guitar.
During the late 1940s and early 1950s, nylon-stringed guitars were being eclipsed in popularity by the steel-string guitar. Some of the younger members of the family wanted to expand into steel strings, but Charles was reluctant to risk the family business on what he considered an uncertain market. In 1956, a new company (Archaic Musical String Manufacturing Co.) began to make steel strings, run by Charles' son, John D'Addario Sr. The company made strings for several of the major guitar makers of the time, including Gretsch, Martin and Guild. In 1962, the two companies were merged under the name Darco.
The guitar had soon become the most popular instrument in the United States, and the Darco company came up with many innovations in the manufacturing of guitar strings, including the first automated equipment to wind strings and the first roundwound bass guitar strings.
In the late 1960s, Darco was approached by Martin Guitars regarding a merger in order to pool resources and development efforts. While the partnership was beneficial for both companies, by 1974 the D'Addario family decided it was time to market strings under their own name, and the J. D'Addario & Company corporation was formed.
Originally located in Lynbrook, New York, the business continued to expand and moved to its current facility in Farmingdale, New York in 1994. The company is still owned and operated by the D'Addario family, with 13 family members among the 900 company employees.