Joseph Leonais was born in the province of Quebec, Canada in 1818. His parents were French and lived on a small farm. When Joe turned eighteen, he left home and moved to Mackinac Island on Lake Michigan. He got a job as a fur trapper.
Because many people were moving to the area, Joe decided to head west. As Bruguier had also done, Joe got a job working for the American Fur Company. He traveled up the Missouri River to Dakota Territory where he would trap furs all winter. In the spring the company would gather all the trappers' furs together and send them down the Missouri River to St. Louis. Only the most trusted employees were given this job. Joe was one of the men that made this trip many times. The men would float down the Missouri through the plains of Dakota to the tree lined bluffs of Iowa. Many times the men would camp below a bluff that had a small wooden cross that marked the grave of Sergeant Floyd from the Lewis and Clark expedition.
Joe married Rosalie Menard daughter of Louis Menard, a fur trapper, and his Indian wife. A year later, in 1852, Joe and his wife decided to settle down. He remembered this good land between the Sioux and Floyd. He stopped by a log cabin and discovered his old friend Bruguier lived there. He purchased from Bruguier a claim for 160 acres of land for $100. This land is today the downtown area of Sioux City.
Legend has it, Bruguier and Leonais celebrated the land deal by having a little party. After having drank too much liquor, Leonais left on his horse. Bruguier worried about his friend riding in such an intoxicated condition and sent his son to try to bring him back. Leonais saw the boy coming and thought he wanted to race, so he set off on his horse as fast as it would go. At top speed the man and his horse crested Prospect Hill and went over the cliff. Joe was lucky, his fall was stopped by a mulberry bush and he was pulled back up to safety by four Indians who had witnessed this amazing event. His horse fell all the way to the bottom and drowned in the river.
Leonais built a cabin near what is now Second and Water streets and began to farm the land, planting corn and trading with Indians in this region. His first of four children was born here in 1853. The family grew in 1854 when Leonais' sister, Mrs. Anna Lapora and her two children moved in with them. Her husband had died in Canada and she came to visit but decided to stay. She became the first white woman to live in Sioux City and later the first white woman to be married here.
In 1854 Doctor Cook arrived and began plotting out the city. He approached Joe to buy his land because of the ideal location. His land was desperately needed to build a levee on so steamboats would have a place to dock. Mrs. Lapora advised Joe not to sell. He listened to her advice and told the doctor no. She realized how important this land was to the development of a city and encouraged Joe not to sell at any price. They could sell the lots themselves. Joe held out until the price of three thousand dollars was offered. He then sold without discussing it with his sister.
Joe and Rosalie had four children. She died during the birth of their fourth child. She was buried on a hill overlooking South Ravine Park in Morningside. There is now a monument there naming her the first bride to die in the city.
Joe remarried twice in his life. He second wife, Victoria Ganon, died in the 1890s. His third wife Rosalia was alive at the time of his death.