A Hero Square will be rededicated this Saturday, Oct. 28 at 11 a.m. to Pvt. Carl H. Alsen, a Dorchester soldier killed in action in France in 1918.

The ceremony will be the culmination of seven years of research and work by Joan Schwerin of Bedford, Mass., who began her mission after learning about Alsen in her parents’ old collection of letters.

Schwerin, a retired tax accountant, foraged through old documents, library books, and online sources to piece together a portrait of the Dorchester soldier.

“I’m a very curious person,” she explains.

Alsen, the son of Swedish immigrants, was born in Lynn, Mass on August 18, 1899. As a teenager his family moved to 11 Spaulding St. in Dorchester, where Alsen attended the Mary Hemenway School.

Alsen lied about his age in order to register with the Massachusetts National Guard on April 2, 1917--the very day President Woodrow Wilson made his speech to Congress requesting a declaration of war against Germany.

Pvt. Alsen was killed in action at the age of 18 on April 12, 1918 during the Battle of Apremont in northeast France. He was posthumously awarded the French Croix de Guerre with gilt star for his bravery in the battle. He was a member of a mortar platoon that staved off a massive German offensive. Alsen’s regiment, the largely Massachusetts-born 104th Infantry 26th Division, known as the “Yankee Division,” was awarded with the Croix de Guerre two weeks after the battle, marking the first time an American regiment had been decorated by a foreign government.

In 1935, Victory Road Park in Dorchester was renamed in Alsen’s honor and a playground was installed on the site bearing his name. After World War II, the site was used for temporary veteran housing, which was later demolished and then taken over by the state. The playground and Alsen’s memorial marker were lost somewhere along the way. This disappearance is what caught Schwerin’s attention.

“It started with me asking the question what happened to the playground,” she says. She soon discovered that the former site of the playground was still listed as a hero’s square.

“It was there the whole time, hidden in plain sight,” says Schwerin.

Saturday’s dedication of the Hero Square will rightfully restore the honor originally bestowed on Pvt. Alsen and memorialize the sacrifice he made for his country a century ago. Several members of his descended family will be in attendance.

Schwerin is just glad to help more people learn about a local hero.

“He was clear he had this enthusiasm and really wanted to serve his country,” said Schwerin. “It’s such a great story, and luckily a lot of people have managed to keep his memory alive for years.”