For Playing for Change, it’s Marley; for the World Orchestra for Peace, it’s Mahler.

Either way, the message is the same: peace through music. This week, the World Orchestra, made up of 95 musicians from 35 countries, will be playing both to commemorate World War II and to celebrate 200 years of peace.

On September 1, the World Orchestra performed in Krakow, Poland, in a concert marking the 70th anniversary of the start of World War II. The program included Mahler’s “Symphony no. 5 in C# Minor”, as well the world premiere of a commissioned piece called “Prelude to Peace,” by Polish composer Krzysztof Penderecki.

The orchestra will follow this somber event with a celebration in Stockholm, Sweden on September 2 at the Baltic Sea Festival. The festival’s theme this year is appropriately named “peace and reconciliation,” chosen for the 200th anniversary of a peace treaty between Sweden and Finland.

The World Orchestra for Peace was founded by the highly influential conductor Georg Solti, a Jewish-Hungarian who was forced to flee his homeland at the start of World War II. He first organized the orchestra at the request of the United Nations to celebrate their 50th anniversary in 1995.

The idea had been brewing in Solti’s mind since a concert at Buckingham Palace three years before, when 13 of the world’s most prolific musicians came together and performed in celebration of his 80th birthday. Solti later said, “I could not escape one very essential idea. Isn’t it amazing that we musicians can produce a united Europe or more… even a united world. Why can’t the politicians?”

Sadly, Solti passed away in 1997, and Valery Gergiev, the Principal Conductor for the London Symphony Orchestra, has led the group ever since, giving concerts in cities like Moscow, Berlin, Beijing, Jerusalem, and Budapest.

The World Orchestra is an elite organization which only admits musicians by invitation. These citizens, representing dozens of cultures and languages, sit side by side, often unable to communicate with words but still in perfect harmony. As Solti said, it would be nice if one day politicians could do the same.