Born in Belfast to a musical family engaged in traditional folk music, McSherry picked up the pipes at an early age and won two All-Ireland championship titles on the instrument by the age of 14. In the '80s, he and family members formed the McSherrys, which became the Celtic folk-rock band Tamalin when John and siblings Tina (vocals), Paul (guitar/Dobro), and Joanne (fiddle) were joined by friend Kevin Dorris (bouzouki/bodhran). The band released the LP Rhythm & Rhyme in 1997.

Meanwhile, Lúnasa had formed in 1996 and settled into the lineup of John McSherry, Kevin Crawford (flute/whistles), Donogh Hennessy (guitar), former Waterboy Trevor Hutchinson (bass), Michael McGoldrick (flute/pipes), and Sean Smyth (fiddle/whistles). They had a hit in their home country with their self-titled debut, also released in 1997. Not wanting to tour, McSherry then left the group's official lineup but still leant pipes to 1999's Otherworld. He and McGoldrick went on to release the duet album At First Light in 2002 before McSherry teamed up with Dónal O'Connor for 2006's Tripswitch. In the meantime, McSherry made a name as a session musician, appearing on albums by the likes of Rod Stewart, Nanci Griffith, Clannad, and the Corrs.

The year 2010 brought the solo album Soma, as well as Six Days in Down with O'Connor and Bob Brozman. The eponymous LP The Olllam arrived in 2012 by a group he formed with Detroit natives Tyler Duncan (guitar, keys, pipes, whistles) and Michael Shimmin (drums). A collaboration with O'Connor and Sean Óg Graham, Ulaid arrived in 2015, and in 2016 McSherry released The Seven Suns, a concept album about Ireland's distant past. It included performances by guests such as McGoldrick and Niamh Dunne. ~ Marcy Donelson