The first settlers of the Lehigh Valley region were Germans who emigrated from earlier settlements along Perkiomen Creek. The earliest settlers arrived in the region over a 20-year period beginning in about 1732. The immigration of the Germans and other European natives, including Swiss and Huguenots, was aided by William Penn and his friends. The land lying south of South Mountain was given to William Penn in 1713 by the Lenni Lenape people. The land of Lehigh County lying between Blue Mountain and the Lehigh Mountains was given to Penn's sons by the Lenni Lenapes in 1732. Emigrants sought the fertile, limestone valley flanking rivers and streams such as Jordan Creek.