Tina Turner married her longtime German boyfriend, Erwin Bach, in a civil ceremony in Switzerland, after dating for 27 years.

Turner, a legendary soul singer, married her music executive boyfriend, who is almost 15 years her junior. They officially tied the knot at the registry office near Zurich, said Markus Ernst, the mayor of Kuesnacht, where Turner owns a lakeside chateau.

The ceremony happened several weeks ago, sometime between late June and early July, ABC News reports.

Swiss newspaper Schweiz am Sonntag reported that stars David Bowie and Sade, as well as talk show host Oprah Winfrey, were among the more than 120 guests who were invited for the private ceremony at the chateau. They stayed at Zurich's finest hotels.

A small concert stage was set up in the chateau's garden and Turner and Bach wrote neighbors to apologize in advance for any noisy disturbances.

Turner requested that all guests wear white, and she wore a gown designed by Giorgio Armani.

According to The Daily Mail, the newlyweds will cement their union this weekend at a Buddhist ceremony on the banks of Lake Zurich, where the couple live.

Why did it take Turner and Bach 27 years to tie the knot? Tina has spoken in the past about her reasoning for not remarrying, after divorcing from her first husband Ike Turner.

"People often ask me why don't I marry," she told Oprah. "I have love. I have a good life. I don't need to interfere with that. For some people, marriage means "You're mine now." That can be the beginning of the failure of a relationship."

She added: "Psychologically, something happens when someone says, "You're my husband or wife. You can't do this or that." It's about ownership. That freedom that two people loving each other and wanting to be together - and being able to leave if anything is wrong - is gone.

"Neither Erwin nor I feel the need to get married. We've been together for 18 years. What would marriage give me that I don't already have? Marriage would be about pleasing the public. Why do I need to please the public if I'm already pleased?"