The idea was hatched in a restaurant in 1989 by two men who lived in the village. Thomas Jensen played bass in Skyline, a regional rock and metal cover band that had worked its way up from pub gigs and biker meets to supporting Extrabreit; Holger Hubner was a DJ with a taste for the same music. They wanted an open-air concert in the local gravel pit, which already served as a gathering place for up to 3,000 members of the No Mercys motorcycle club and therefore came with both a venue and an audience. Skyline's drummer Andreas Goser and Jensen's brother Jorg were recruited to help. The first festival ran over two days, 24 and 25 August 1990, and barely 800 people came. Every band was German. The lighting rig was built on a trailer borrowed from a local haulier, and the stage was homemade.

Growth was slow and stubbornly amateur. Attendance reached 1,300 in 1991, the year Mark Ramsauer drew the cow-skull logo - a nod both to the cattle meadow the festival stood on and to the organisers' own description of themselves as boys from the village. Ticket orders were handled privately by Andreas Goser's mother, Regina, until August 1994; friendly motorcycle clubs did security until 1996. The programme turned international in 1992 with Blind Guardian and Saxon, and the same year brought a professional stage, proper lighting and a first sponsor. By 1994, its fifth anniversary, income and expenditure finally balanced, on some 4,500 tickets sold, and national media began to notice. Then the village pushed back: after the crowds of 1996, residents objected to an event that size in the gravel pit, and the farmer Uwe Trede offered his own land instead and helped acquire more. The move made everything that followed possible. In 1997 a third stage went up and attendance hit 10,000 for the first time.

In 2006 the organisers declared that 62,500 visitors were the limit of what was possible. They were wrong, and the ticketing history since reads like a series of records nobody expected. The festival sold out ten years running from 2006 to 2015. An X-Mas package put on sale on 8 August 2011, days after that year's festival ended, was gone in 45 minutes; tickets for 2015 went in twelve hours; the 2016 Christmas allocation lasted twenty minutes and buried the ticket agency's servers. Then, abruptly, 2017 took 309 days to clear - a wobble that set off much speculation about prices and security fears - before the pattern reasserted itself. The 2023 edition sold out in about five hours, the 2024 edition in 4.9 hours. In 2025 it took 57 days, which for any other festival would be a triumph.

Running a city of 85,000 on farmland requires industrial logistics. The infield around the main stages covers 43,000 square metres; the wider site holds more than 1,300 toilets and almost 500 showers. Around 2,200 truckloads of equipment come in, 75 of them carrying a thousand tonnes of stage hardware, with construction taking about seven days and the teardown five. Since 2014 the site has drawn 12 megawatts, roughly the demand of a town of 70,000, backed by 40 diesel generators and looked after by 25 electricians. Medical cover is provided by the Wacken Rescue Squad, staffed by volunteers from relief organisations across Germany and numbering around 270 people at peak, supported by more than ten ambulances and mobile intensive care units. In 2013 roughly 3,300 people were treated by about 500 medics. Police classify the festival as secure by the standards of events this size; the persistent problem is theft rather than violence.

What is unusual about Wacken is not the scale but the truce. The relationship is transactional in the best sense - local shops and restaurants sell many times their normal volume during festival week, and the village pub ran a beer garden with 3,500 seats until it went insolvent in 2012, whereupon the festival organisers bought it and reopened it. Friction has been handled with a similar practicality. A noise complaint brought by residents before the Schleswig administrative court ended in an out-of-court settlement in January 2013: if the average level exceeds 70 decibels, the organisers pay 1,000 euros to the community, which passes it to charity. The town signs used to be stolen so often that they were replaced during the festival with plastic ones reading Heavy Metal Town, or simply bolted down harder; local shops now sell bags printed with the sign and the line that this one you may keep. And in 2013, for the parish church's 150th anniversary, the festival team and the congregation staged a Full Metal Church - a concert by the folk band Faun framed by two readings and sermons. Both the concert and the services were hopelessly overcrowded with festival-goers.