What is happening!? With no mention of St. Patrick's Day across McDonald's US channels the green minty Shamrock Shake has launched in Ireland for 2020. 

It seems strange to us that the McDonald's St. Patrick's Day limited-edition drink, the Shamrock Shake, is available in Ireland ahead of the United States this year. While obviously Ireland is the center of all things green, white and gold this time of year we find it strange because the McDonald's Shamrock Shake was in fact invented in Connecticut. 

The Shamrock Shake from McDonald’s Ireland launched in late January to kick start the St Patrick’s Day celebrations early. The marvellous milkshake will be available for a limited time only in Ireland (until Mar 24).

Read more: Why is Saint Patrick's Day celebrated on March 17?

It seems Americans will have to be patient and wait until March 2020 to enjoy their McDonald's St. Patrick's Day treat. 

Whenever you manage to pick up your Shamrock Shake the history of this green St. Patrick's Day treat deserves to be remembered. 

It all happened back when Harold Rosen, who owned a McDonald's in Connecticut, invented the popular holiday drink in 1966.

The McDonald's website says, "It all began with a little girl, a football team, and a visionary doctor."

The Philadelphia Eagles tight end Fred Hill's daughter was diagnosed with leukemia and began treatment. The Hill family were camping out in waiting rooms in hospitals and saw other families doing the same. They realized that many families who were traveling long distances to visit their sick family members had nowhere to stay and could not afford hotel rooms. The Hill family did something about it.

Hill and his team decided to raise some funds. The team's general manager, Jim Murray, called a friend in McDonald's advertising and suggested the team on the next promotional push. It just happened to be St. Patrick's Day.

Rogers Merchandising in Chicago created the shake and James Byrne, the executive artist at the firm, used a family recipe.

The Shamrock Shake raised enough money to buy a four-story house which was the first Ronald McDonald House.

We just love it. Talk about making a difference. 

Read more: Homemade alcoholic McDonald's Shamrock Shake recipe