Early uses of amplified distortion
The first guitar amplifiers were relatively low-fidelity, and would often produce distortion when their volume (gain) was increased beyond their design limit or if they sustained minor damage. Around 1945, Western-swing guitarist Junior Barnard began experimenting with a rudimentary humbucker pick-up and a
small amplifier to obtain his signature "low-down and dirty" bluesy sound. Many electric blues guitarists, including Chicago bluesmen such as Elmore James and Buddy Guy, experimented in order to get a guitar sound that paralleled the rawness of blues singers such as Muddy Waters and Howlin' Wolf, replacing often their originals with the powerful Valco "Chicagoan" pick-ups, originally created for lap-steel,
to obtain a louder and fatter tone. In early rock music, Goree Carter's "Rock Awhile" (1949) featured an over-driven electric guitar style similar to that of Chuck Berry several years later, as well as Joe Hill Louis' "Boogie in the Park" (1950).
In the early 1950s, pioneering rock guitarist Willie Johnson of Howlin' Wolf′s band began deliberately increasing gain beyond its intended levels to produce "warm" distorted sounds. Guitar Slim also experimented with distorted overtones, which can be heard in his hit electric blues song "The Things That I Used to Do" (1953). Chuck Berry's 1955 classic "Maybellene" features a guitar solo with warm overtones created by his small valve amplifier. Pat Hare produced heavily distorted power chords on his electric guitar for records such as James Cotton's "Cotton Crop Blues" (1954) as well as his own "I'm Gonna Murder My Baby" (1954), creating "a grittier, nastier, more ferocious electric guitar sound," accomplished by turning the volume knob on his amplifier "all the way to the right until the speaker was screaming."
In the mid-1950s, guitar distortion sounds started to evolve based on sounds created earlier in the decade by accidental damage to amps, such as in the popular early recording of the 1951 Ike Turner and the Kings of Rhythm song "Rocket 88", where guitarist Willie Kizart used a vacuum tube amplifier that had a speaker cone slightly damaged in transport.  Rock guitarists began intentionally "doctoring" amplifiers and speakers in order to emulate this form of distortion. In 1956, guitarist Paul Burlison of the Johnny Burnette Trio deliberately dislodged a vacuum tube in his amplifier to record "The Train Kept A-Rollin" after a reviewer raved about the sound Burlison's damaged amplifier produced during a live performance. According to other sources Burlison's amp had a partially broken loudspeaker cone. Pop-oriented producers were horrified by that eerie "two-tone" sound, quite clean on trebles but strongly distorted on basses, but Burnette insisted to publish the sessions, arguing that "that guitar sounds like a nice horn section".
In the late 1950s, Guitarist Link Wray began intentionally manipulating his amplifiers' vacuum tubes to create a "noisy" and "dirty" sound for his solos after a similarly accidental discovery. Wray also poked holes in his speaker cones with pencils to further distort his tone, used electronic echo chambers (then usually employed by singers), the recent powerful and "fat" Gibson humbucker pickups, and controlled "feedback" (Larsen effect). The resultant sound can be heard on his highly influential 1958 instrumental, "Rumble" and Rawhide.
1960s: fuzz, distortion, and introduction of commercial devices
In 1961, Grady Martin scored a hit with a fuzzy tone caused by a faulty preamplifier that distorted his guitar playing on the Marty Robbins song "Don't Worry". Later that year Martin recorded an instrumental tune under his own name, using the same faulty preamp. The song, on the Decca label, was called "The Fuzz." Martin is generally credited as the discoverer of the "fuzz effect." 
Big Muff fuzzboxes: a NYC re-issue (L) and a Russian Sovtek version (R)
Shortly thereafter, the American instrumental rock band The Ventures asked their friend, session musician and electronics enthusiast Orville "Red" Rhodes for help recreating the Grady Martin "fuzz" sound. Rhodes offered The Ventures a fuzzbox he had made, which they used to record "2000 Pound Bee" in 1962. The best-known early commercial distortion circuit was the Maestro FZ-1 Fuzz-Tone, manufactured by Gibson, released in 1962.
Also in the early 1960s, surf rock guitarist Dick Dale, who produced hits such as "Let's Go Trippin'" (1961) and "Misirlou" (1962), worked closely with Fender to push the limits of electric amplification technology, producing the first 100-watt guitar amplifier.
In 1964, a fuzzy and somewhat distorted sound gained widespread popularity after guitarist Dave Davies of The Kinks used a razor blade to slash his speaker cones for the band's single "You Really Got Me".
In May 1965 Keith Richards used a Gibson Maestro FZ-1 Fuzz-Tone to record "(I Can't Get No) Satisfaction". The song's success greatly boosted sales of the device, and all available stock sold out by the end of 1965. Other early fuzzboxes include the Mosrite FuzzRITE and Arbiter Group Fuzz Face used by Jimi Hendrix, the Electro-Harmonix Big Muff Pi used by Hendrix and Carlos Santana, and the Vox Tone Bender used by Paul McCartney to play fuzz bass on "Think for Yourself" and other Beatles recordings.
In 1966, Jim Marshall of the British company Marshall Amplification began modifying the electronic circuitry of his amplifiers so as to achieve a "brighter, louder" sound and fuller distortion capabilities.
In the late 1960s and early 1970s hard rock bands such as Deep Purple, Led Zeppelin and Black Sabbath forged what would eventually become the heavy metal sound through a combined use of high volumes and heavy distortion.