August 25, 1737: An agreement was signed on this date by Thomas Penn and Munsee Chiefs Manawkyhickon and Nutimus. The agreement called for Indian lands to be sold along the Delaware river for the distance that a man could walk in a day and a half. This would be called the "Walking Purchase" and would be performed on September 19, 1737.
From: Lee Sultzman's Delaware History
In 1737 Pennsylvania authorities "found" the infamous Walking Purchase agreement, a treaty supposedly signed in 1686 in which the Lenape ceded the land between the junction of Delaware and Lehigh Rivers as far west as a man could walk in a day and a half (about 40 miles). This was bad enough, but Penn's son Thomas hired three of the fastest men in the colony and offered a prize to the one who could cover the greatest distance. Running on a prepared path, the winner went twice the distance the Delaware had anticipated which cost them most of the Lehigh Valley. Realizing they had been cheated, the Delaware expected the Iroquois to defend their interests, but the Iroquois were furious that the Delaware had signed a treaty without their permission. Pennsylvania also took the precaution of bribing them to stay angry and enforce the agreement. The ultimate humiliation came during a 1742 meeting of the Delaware, Iroquois and the Pennsylvania governor. When the Delaware sachem Nutimus rose to protest the Walking Purchase, the Iroquois representative Canasatego silenced him with, "We conquered you. You are women; we made women of you. Give up claims to your old lands and move west. Never attempt to sell land again. Now get out."