They made no move to halt him, for the man's reputation for toughness, violence and courage had spread through the Indian tribes and they were afraid of him. In fact, there was no one within range of his reputation, white or Indian, who failed to have a healthy respect for him." (Louise Zerschling, SC Journal 1954)

William Thompson was born in a small town in Illinois in 1818. He grew up, married and lived there until 1847 when his wife died. He enlisted in the United States Army and fought in the Mexican War.

After the war, he was discharged from the army and headed up the Missouri. When he got to Floyd's Bluff, he decided this was the place he would stay. Although Thompson was the first person to settle in the area, it was well known because of the marker for Sergeant Floyd. Later in the fall his brother Charles came to visit. He stayed all winter.

The following years several French trappers and their Indian wives built cabins in the area. This did not please William because he liked being alone. He did not like people or the laws they made. In the past he had had trouble following the law. But as long as people were coming he decided to make the best of it. He decided to found a town called Thompsontown and sell lots to people to earn money.

In 1852 one of the Frenchmen, a Mr. LaCharite had a dance at his home. Thompson, the French and Indian neighbors attended the party. An Indian agent named Major Norwood also attended. The Major was planning on marrying Sophie Menard and Thompson was dancing with her. Thompson decided to make fun of Norwood by taking the wig off Norwood's head. This made Norwood very mad and he stabbed William slightly injuring him. Thompson left for home and Norwood, realizing the trouble he was in tried to escape. Thompson caught up with him and crushed his skull in with the butt of his rifle, killing Norwood. He was tried for murder but never punished because people were so afraid of him.

He had his own set of values. In the winter of 1855, Thompson had an unusually large supply of flour on hand. The settlers needed this flour to make bread. He was the only one in the area with extra to sell. He could have raised his prices but he refused. All people were allowed to buy the wheat at the standard price.

In 1858 he traveled to Kanesville (Council Bluff) to register a plat of his town he now named Floyd's Bluff, but the town never became a success. He did have a chance to have his town developed when Dr. John Cook offered to purchase his land to build Sioux City. Thompson was too stubborn and wanted too much money so Cook was forced to look somewhere else.

He continued to live on his land, marrying again in 1869 to Martha Jane Blackwell. He died in 1879 at the age of 61.