One of Duluth's most famous murders was 45 years ago this week

DULUTH — Monday marks 45 years since an elderly heiress from one of the region's most high-profile families and a retired night nurse who was working a pick-up shift were found slain in the Congdon mansion — a story that remains one of the city's most buzzed about murders.

On June 27, 1977, Elisabeth Congdon — at 83, the last living child of Northern Minnesota mining magnate Chester Congdon and his wife, Clara — was found smothered in her bed in the family's 39-room Jacobean mansion on the shore of Lake Superior. Nurse Velma Pietila, 66, who had recently retired but was subbing for a former colleague, was found on the staircase — beaten to death with a candlestick.

The women's bodies were discovered when the morning nurse showed up at the mansion for her shift.

Though the case was first treated as a burglary, signs pointed to Elisabeth Congdon's adopted daughter Marjorie Caldwell and her husband Roger Caldwell. They were struggling with severe financial problems at the time and had moved to Colorado with a plan for a horse ranch. There was a more than $8 million inheritance on the line.

Roger Caldwell was ultimately convicted; Marjorie, charged with plotting the murders, was acquitted.

Roger Caldwell was set to serve two life sentences, but the ruling was overturned in the early 1980s and he was released from prison — contingent on a confession that might or might not have been wholly true.

"An extremely wealthy person was murdered," he told Joe Kimball of the Star Tribune in 1987. "Someone had to pay. My wife was the most hated member of the family and the only way they could get to her was through me."

He was in poor health and living in his hometown of Latrobe, Pa., in 1988 when he killed himself.

Marjorie Caldwell's adopted sister, Jennifer Congdon Johnson, who died in 2017, told Kimball that she believed Marjorie was directly involved.

There are other crimes on her record though, including bigamy. She married Wally Hagen, though seemingly never divorced Roger Caldwell. Kimball wrote in a column published in 2017 in the Star Tribune, that Caldwell receives $50,000 a year from the inheritance. She turns 90 next month and is believed to be living in Arizona.

Glensheen mansion remains a popular local attraction, though it's the architecture, scenic gardens and fountains, and the Congdon-era interior styles that are pushed as a reason to tour the estate. Most visitors come for the museum, executive director Dustin Heckman said earlier this month, though some drop by because of curiosity about the murders.

The mansion's keepers do not seem to have anything planned to commemorate Elisabeth Congdon and Velma Pietila on Monday.

On the 40th anniversary, local publisher Tony Dierckins alongside authors John DeSanto, a retired St. Louis County prosecutor, and former Duluth News Tribune reporter Gail Feichtinger offered a presentation about the murders and Marjorie Caldwell Hagen at the mansion. The three speakers were involved with the book "Will to Murder: The True Story Behind the Crimes and Trials Surrounding the Glensheen Killings." The book remains the most popular book Dierckins has published, he said recently.