La Demoiselle, also called "Old Briton" by the British, was a Miami leader based at Pickawillany during the mid-1700s. La Demoiselle refused to trade with French traders, who often engaged in price gouging, choosing instead to allow British traders to set up a post at Pickawillany near what is now Piqua, Ohio. In 1750, Celeron de Bienville unsuccessfully tried to persuade the Miamis to return to a trading partnership with the French. The following year, the French raided the village, killing two Miamis and capturing two British traders, but not changing La Demoiselle's attitude towards the French. In 1752, the French tried again, encouraging their American Indian allies to attack the town and take the British traders prisoner.
During this assault on Pickawillany, the attackers took hostage the Miami women who had been out working in the fields. The men, including both British traders and Miamis, blockaded themselves within the town's fortifications. Hoping that their adversaries would show them mercy, the Miami warriors eventually surrendered and turned over the British traders to their attackers. Most of the Miamis survived, but the French-supported American Indians killed La Demoiselle.
After the attack on Pickawillany and La Demoiselle's death, the Miami abandoned Pickawillany and moved westward into modern-day Indiana. The British did little to retaliate quickly against the attack. The Miamis, as well as other Ohio Indians, began to believe that an alliance with the French might be more advantageous than an alliance with the British, who were either unwilling or unable to protect their allies.
- Anson, Bert. The Miami Indians. Norman: University of Oklahoma Press, 1970.
- Hurt, R. Douglas. The Ohio Frontier: Crucible of the Old Northwest, 1720-1830. Bloomington, IN: Indiana University Press, 1996.