Antoine Le Claire (also LeClaire; December 15, 1797 – September 25, 1861) was an American military interpreter, businessman, philanthropist, and principal founder of Davenport, Iowa.

Le Claire was born on December 15, 1797, in present-day St. Joseph, Michigan, then in the Northwest Territory. His father, François Le Claire, was French Canadian and came to the Americas with Lafayette. His mother was a Native American from the Potawatomi tribe. His father opened a trading post in Milwaukee, Wisconsin, where he traded with several Native American tribes. François supported the side of the United States during the War of 1812. He was subsequently captured by the territorial militia at his trading post in Peoria, Illinois, and held as a prisoner in Alton, Illinois. While his father was imprisoned, Antoine met General William Clark who was impressed with Le Claire's faculty with languages; Clark sent Antoine to school to improve his English and he entered government service. Le Claire spoke English, French, Spanish, and a dozen Native American dialects. He came to Fort Armstrong in 1818, where he became the interpreter for Colonel George Davenport. A short time later, he moved to Peoria, where he met and married his wife Marguerite LePage in 1820. She was born on October 16, 1802, in Portage des Sioux, St. Charles County, Missouri. She was the daughter of a French Canadian, Antoine LePage, and the granddaughter of the Sauk chief Acoqua. After Peoria the Le Claires spent a short time in Arkansas where he observed the movements of Native Americans before moving back to Fort Armstrong in 1827.^{[citation needed]}

In 1832, at the end of the Black Hawk War, Le Claire was present at the peace treaty signing as an interpreter. Sauk and Meskwaki territories west of the Mississippi River were purchased by the United States government. Because he was respected by the Native Americans, the Le Claires were given three parcels of land. One of the parcels was at the head of the Rock Island Rapids on the west side of the river. The second was given to Marguerite by Keokuk, the Sauk chief. It was also located on the west side of the river and had been the location of the Meskwaki village. Keokuk stipulated that Le Claire build a house on the spot where the peace treaty was signed, or lose the land. After the United States Congress approved the peace treaty in 1833, Le Claire built a house, known as the Treaty House. The third parcel of land was given by the Potawatomie on the Illinois side of the river where present day Moline, Illinois, is situated.

Le Claire was named the postmaster and the justice of the peace in 1833. His jurisdiction included all the lands that had been included in the Black Hawk Purchase. He was responsible for resolving disputes between the Native Americans and the white settlers. He generally took a hands-off approach which the independent-minded settlers found appealing. In 1834 he established the area's first ferry service across the river. LeClaire also served as Black Hawk's translator when the Sauk warrior wrote his memoirs.

George Davenport gathered a group of investors at his home on February 23, 1836, to create a company in order to develop a new town. It was to be located on the Iowa side of the Mississippi River opposite the town of Stevenson, Illinois, which is now the city of Rock Island. Antoine Le Claire was part of the group. While he owned a great deal of land, he did not have a great deal of money. The other investors paid him $1,750 for the site that now lies between the river and Seventh Street and between Harrison Street to just past Warren Street.

While Le Claire was the driving force in the development of Davenport, the town was not named for him. Not only did he not have enough money to develop buildings on the land, but he was also a half-breed with a French surname and a devout Catholic. The other investors had English surnames, money to invest and government contracts. George Davenport also failed to have his name attached to the new town across the river (Stevenson), and so the town on the Iowa side of the river was named after him.

Le Claire had the town laid out in the conventional fashion of a grid pattern of 36 squares. Three of the squares were set aside for public squares: Lafayette Square, which is a public park today; Bolivar Square, site of the Scott County Courthouse; and Washington Square, present site of the downtown YMCA. The levee along the river was also left open for public use. The east–west streets but one were named for Native American tribes: Sac, Fox (another name for the Meskwaki), Ottawa, Chippewa, and Potawatomie. Later those streets would be renamed Second through Sixth Streets. Front Street, now River Drive, was along the levee. The north–south streets retain their original names: Ripley, Scott, Western, Gaines, Brown and Warren.

Le Claire joined with George Davenport to develop the first public house in the area, which was named the Le Claire House. He also established the first foundry in the young town, and with A. C. Fulton he built the first mill. He was involved with a group of investors who brought the railroad to Davenport in the 1850s. On his property north of the Rock Island Rapids Le Claire owned and operated a sandstone quarry. Stone from this quarry was used for the Clock Tower on Rock Island Arsenal, the first buildings on the Augustana College campus in Rock Island, and the abutments on the Government Bridge.