Prior to forming Flogging Molly, Dublin-born Dave King was the lead singer for the heavy metal band Fastway featuring guitarist "Fast" Eddie Clarke of Motörhead in the early to mid-1980s.

He later fronted a hard rock band called Katmandu (1991), featuring Mandy Meyer of Krokus and Asia on guitars.

In 1993, King met violin player Bridget Regan, guitarist Ted Hutt, bassist Jeff Peters and drummer Paul Crowder,[2] and put together a rock band with a Celtic music influence.

Putting King's poetic lyrics to rocking melodies, they played weekly at a Los Angeles pub called Molly Malone's, building a small but loyal following.

In 2016, from March 18 to 21, the second yearly cruise took the same itinerary on the same ship and hosted, among others, Rancid, Fishbone, Frank Turner, Street Dogs and The Tossers.

The guests invited by the band were NOFX, DeVotchKa, Less Than Jake, The English Beat, The Skatalites, The Bouncing Souls, Dylan Walshe and many others.

On August 21, 2017, the band announced that the 2018 cruise would take place April 20–23, leaving from Miami, sailing to Key West and to Great Stirrup Cay.

The Salty Dog Cruise 2023 ran November 8–13, sailing from Miami to Harvest Caye, Belize, and Costa Maya, Mexico.

The line-up included Flogging Molly, Pennywise, Stiff Little Fingers, The Vandals, and Gorilla Biscuits, among others, with a Port of Miami kickoff show featuring The Interrupters.

[18] In late November 2023, the band announced the next Salty Dog Cruise, set for February 17–22, 2025, sailing from Miami to Grand Cayman, and Ochos Rios, Jamaica.

[citation needed] Their music ranges from boisterous Celtic punk, like the pirate-themed "Salty Dog", "Cruel Mistress", and "Seven Deadly Sins", or the defiant "What's Left of the Flag", "Drunken Lullabies", and "Rebels of the Sacred Heart", to more somber songs like "Far Away Boys", "The Son Never Shines (On Closed Doors)", "Life in a Tenement Square", and "Float".

Lyrics typically touch on subjects such as Ireland and its history, drinking, poverty, politics, love, and death and include several references to the Catholic Church.