The St. Croix Valley was opened for development in 1838, after treaties between the united States government and the Ojibwa and dakota Indians were signed. Speculators could now harvest the century-old white pine stands along the st.Croix and its tributaries. The first steamboat, the palmyra, came up the St. Croix River in July 1838 carrying the supplies and personnel necessary to build a sawmill at the head of navigation on the river where St. Croix Falls and Taylors Falls are located today. It was on a trip back from st. Croix Falls to Stillwater that William Kent and his men discovered Cascade Falls and claimed it for energy that it would create to power their mills. They saw the potential power this falling water could create if it were properly harnessed. This settlement like all others needed a name and towns are generally named after something or someone, Osceola, was no different and during this period many towns, villages, or counties were named and have retained the name of Osceola.

Chief Osceola led the Seminole Indians in Florida during the Second Seminole War (1835-1842). In 1837, he agreed to meet with U.S. Troops under a flag of truce. General Thomas jessup violated this truce, and Chief Osceola was captured and transferred to Fort Moultrie prison in South Carolina, where he died a short time later. The trickery of General Jessup outraged many Americans and resulted in the creation of many towns and counties bearing the name of Osceola.

All indications show that when Osceola was incorporated in 1844 the new settlement was called Osceola, out of respect for Chief Osceola and his plight with the U.S. Government. When Polk County was organized in 1853 the name was changed to leRoy in honor of LeRoy Hubble, the first white man killed at this settlement. Mr. Hubble was struck by a falling tree linb, while cutting timber.

In 1858, some residents wanted to change the name back to Osceola, but to comply with postal regulations; the name of Osceola mills was adopted, because there was already another town by the name of Osceola in Southwestern Wisconsin. The word Mills was dropped in 1897, after the other town was nearly destroyed when an epidemic killed the majority of its residents. Recorded history shows that for a short period of time sometime between the years of 1853 and 1858, the town was also called Bluffville.

In the very beginning of the saw mill days Osceola consisted of four buildings located at the river level, all these buildings are now gone, but it was near them that the first Steamboat built on the st. Croix, the Osceola, was built in 1854. Unfortunately, the boat drew too much water for the shallow St. Croix river and was on the river only one year before going to the mississippi River to work. Steamboats were the lifeblood of the St. Croix River Valley until the early 1900's when the railroads began providing Osceola and the other St. Croix River towns with year round freight and passenger service.