This moraine was formed by rocks and sediments dropped by the Wadena Lobe of the Laurentide Ice Sheet 30,000 years ago during the last glacial period.

[5] Prior to European settlement the area would have borne tallgrass prairie, with groves of trees growing where the lakes blocked some of the advancing wildfires.

[3]: 28  Other wildflowers include nodding trillium, large-flowered bellwort, Dutchman's breeches, bloodroot, jack-in-the-pulpit, and starry false Solomon seal.

[3]: 28 Mammals most commonly found in the park are white-tailed deer, groundhogs, minks, foxes, squirrels, and eastern chipmunks.

[5] Monson Lake State Park is located on a major corridor of the Mississippi Flyway and attracts a variety of birds.

Regionally threatened or uncommon species include Henslow's sparrows, American white pelicans, Forster's terns, Franklin's gulls, horned grebes, and trumpeter swans.

[3]: 27 At the time of the most recent survey in 2005, Monson Lake was found to have good water clarity and low to moderate nutrient pollution.

[4] Monson Lake does experience cyanobacteria blooms in summer, but is free of Eurasian water milfoil and other invasive aquatic plants.

[3]: 23 Three archaeological sites demonstrate that the future park was occupied by Native Americans at least as long ago as the Woodland period (1000 BCE – 1000 CE).

Excavation revealed stone tools including obsidian from the Great Plains, flint from the Knife River in North Dakota, and quartzite from near Hixton, Wisconsin, suggesting a wide trade network.

[3]: 35 When Anders and Daniel Broberg, immigrant brothers from Sweden, purchased 160 acres (65 ha) on July 15, 1861, it was at the very edge of the frontier.

[6] However the growing Euro-American population was making it increasingly difficult for the native Dakota people to pursue their traditional lifestyle.

Resettlement on reservations, treaty violations by the United States, and late or unfair annuity payments by Indian agents caused increasing hunger and hardship among the Dakota.

[7] On the morning of Wednesday, August 20, 1862, most residents in the West Lake Settlement were unaware that violence had broken out between Dakota and white settlers three days earlier.

[6] The notion of preserving the Broberg cabin site as a park came to a local resident named Ole Ellingboe on August 20, 1926, the 64th anniversary of the attack.

The Monson Lake Memorial Association continued to hold wildly popular annual events through the Great Depression, marked by speeches, plays, music, and refreshments.

During the Great Depression, the Franklin D. Roosevelt administration funded public works projects to ease unemployment, and park development was a significant focus.

[3]: 36  Since low visitation has never spurred significant alterations, it is the only Minnesota state park that remains nearly unchanged from its original development.

[2] In 1956 the original name Monson Lake Memorial State Park was shortened by officially dropping the word 'memorial.

'[6] Additional developments over the years included staff facilities, showers in the Sanitation Building, a boat ramp, and interpretive signage.

In the mid-2000s decade, the owners of an undeveloped hunting retreat to the east approached the park about selling to the state rather than a real estate developer.

[12] Activities at Monson Lake State Park include birdwatching, camping, canoeing, fishing, hiking, and picnicking.

[3]: 43  Game fish in Monson Lake are walleye, northern pike, largemouth bass, black crappie, yellow perch, and bluegill.