Brothers Noel and Mike Hogan started the band in 1989 and rose to international fame with their debut album "Everybody Else is Doing it, So Why Can’t We?", becoming the most successful rock act of the 90s. They have sold over 14.5 million albums in the United States alone, and have had four albums in the top 20 of the Billboard 200 chart.
The band consists of four members, lead by vocalist Dolores O'Riordan.
Other performers at this year's festival will be disclosed in the next couple of weeks, the organizers said.
Õllesummer will take place from July 6 to 9 on the historical Tallinn Song Festival Grounds, which each year brings together hundreds of local artists and performers from over the world.