Thanks to a 149-year-old "tin box" time capsule and a 10-month-old master's thesis, we now know about a short-lived, secret society in Mankato that was bent on banishing a peaceful tribe of American Indians in 1863.

Made up of Mankato civic leaders, the "Knights of the Forest" pledged "to use every exertion and influence" to remove the Ho-Chunk people — also known as Winnebagos — from 200,000 acres along the Blue Earth River. Never mind that the Ho-Chunk stayed out of the U.S.-Dakota War in 1862. There were profits to be amassed from their prime reservation land south of Mankato.

Planting time capsules in cornerstones of new public buildings, amid festive ceremonies, was common in 1869. More than 1,000 people showed up that June 22 as a procession paraded down Mankato's main street to the then-new Old Main building at Mankato Normal School — today known as Minnesota State University, Mankato.

The capsule's contents, including business cards and newspapers, were read aloud before a musical performance. That capsule was only opened twice in the century that followed: after a 1922 fire and in 1968 during the school's centennial celebration.

But in 2004, a long-buried Knights of the Forest document was unearthed when the capsule's contents were first listed online. It included a membership oath and initiation rites aimed at bringing men "together as brothers" determined "to banish forever from our beautiful State every Indian who now desecrates our soil."

In her May 2017 master's of public history thesis, St. Cloud State librarian Catherine Coats says: "Compelling evidence of Minnesota's unexamined history of hate was locked away in that time capsule along with the ritual document that day" in 1869.

"The Ho-Chunk people were innocent victims of Mankato profiteers' prosperity," Coats said. "Some Knights of the Forest members lived comfortably in Mankato as lawyers, businessmen, and civic leaders for the rest of their lives. Years later, members would sometimes recognize each other via the group's secret grips, passwords, and hand signs."

While the Knights' oath called for ridding the state of all its indigenous people, Coats explains how the Mankato secret society zeroed in on the Ho-Chunk.

An 1886 Mankato newspaper article detailed the Knights' violent nature — "a certain number of men whose duty was to lie in ambush on the outskirts of the Winnebago Reservation, and shoot any Indian who might be observed outside the lines."

They weren't concerned about the Ojibwe living Up North. And the Dakota people had been locked up at Fort Snelling as the first step in the forced exile after the six-week war in 1862, when Gov. Alexander Ramsey told the Legislature that all Dakota "must be exterminated or driven forever beyond the borders of Minnesota."

To many history buffs, the U.S.-Dakota War ended when 38 Dakota men were hanged in Mankato the day after Christmas, 1862. At least three members of the Knights of the Forest were eyewitnesses to the largest mass execution in U.S. history, according to Coats' exhaustive research. Her thesis shows how the acrimony spilled into 1863, when the Knights of the Forest formed within weeks of the hanging.

In "the shadow of that terrible event, the Knights of the Forest perpetuated a deeper, longer hatred," Coats concluded.

The Knights didn't last long, disbanding within months. Congress approved a federal order on Feb. 21, 1863, ordering the Ho-Chunk to move to a barren tract of land along the Missouri River at Crow Creek in what would become South Dakota. More than 550 Ho-Chunk died in the hostile conditions of their relocation.

In her 133-page thesis, Coats names names — unmasking the men behind what was supposed to be a secret group. One of them was Charles A. Chapman, a Harvard-educated son of Welsh immigrants who moved from Massachusetts to become an early Mankato land surveyor, city engineer and Blue Earth County auditor.

"Although they claimed to be shrouded in secrecy, he clearly wanted the organization to be remembered in history," Coats said.

In 1916 — four years before he died in his late 80s — Chapman bragged to a Mankato newspaper about his group's influence: "Notwithstanding the oath of secrecy, hints of the organization got out and went even to government circles in Washington … until the U.S. Government began to take notice. …"

In his writings from 1878 and 1902, Chapman called the peaceful Ho-Chunks a "miserable … drawback to the prosperity" of Blue Earth County.

Another Knight of the Forest, John Meagher, left Ireland at 11 and worked as an Illinois tinsmith's apprentice before buying a Mankato hardware store in 1861. Profiting from the war that erupted the next year, he would become a bank president by 1872.

A third Knight, Asa Barney, was a New Yorker who worked as a bookkeeper in Mankato starting in 1857. All profited by achieving their group's avowed goal: removing the Ho-Chunk from Blue Earth County. Barney and his brother, Sheldon, for example, appear on government land patents for their purchase of "Winnebago Lands."

"The Knights are a piece of the story," Coats said, "that must gain a more prominent place in U.S.-Dakota War history."

Curt Brown's tales about Minnesota's history appear each Sunday. Readers can send him ideas and suggestions at His new book looks at 1918 Minnesota, when flu, war and fires converged: