1. The shakes were first launched in the U.S. in 1970 and were initially called the “St. Patrick’s Day Green Milkshake” before adopting the name “Shamrock Shake”.
2. Harold Rosen, a McDonald’s franchisee owner in Enfield, Connecticut, claimed to have invented the shake in 1966. The McDonald’s Corporation has disputed Rosen’s claim.
3. In 1978, McDonald’s introduced Uncle O’Grimacey (the Irish uncle of Grimace) as way to promote the shakes. The character was phased out in the early ‘80s.
4. McDonald’s introduced the Shamrock Sundae in 1980.
But, due to poor sales, the sundae was discontinued after one year.
5. The Shamrock Shake and the Philadelphia Eagles led the creation of the Ronald McDonald House.
In 1974, Philadelphia Eagles tight end Fred Hill’s daughter, Kim, was being treated for leukemia. He and his wife, Fran, camped at hospital benches and watched other parents and families of seriously ill children do the same thing. Often times the families of children receiving medical treatment couldn’t even afford hotel rooms.
The Hills knew they could find a way help out these parents. They asked the Eagle’s to help Dr. Audrey Evans, head of the pediatric oncology unit at Children’s Hospital of Philadelphia, raise money to build a “home away from home” for families of children being treated at her hospital.
The Hills and the Eagle’s set up the philanthropic program Eagles Fly for Leukemia and began working with a local McDonald’s advertising agency as a way to raise money.
Eagles Fly for Leukemia and McDonald’s decided to fundraise on their next promotion, which happened to be Shamrock Shakes. The shakes and the Eagles colors were both green, making it a prefect tie-in. After a week-long promotion around the Shamrock Shake, enough funds were raised to help buy an old four-story, seven-bedroom house. It opened in 1974 as the first Ronald McDonald House.
6. Shamrock Shakes were discontinued nationally in the early ‘90s. Its cult following and huge Internet presence led to it being re-introduced in the late-‘00s.
The Shamrock Shake didn’t become fully available at 14,000 McDonald’s locations untill 2012.