Fell was born in rural southeastern Chester County, Pennsylvania, to Quaker parents of modest means, Rebecca (Roman) and Jesse Fell. He attended local Friends schools as well as a private boy's academy and briefly taught in local public schools before migrating to Ohio to study law in 1828. In 1831 Fell moved to Illinois, opening Bloomington's first law offices and beginning his career in real estate. Fell was especially active during the Illinois land boom in the late 1830s; with James Allin, Fell co-founded the town of Clinton, Illinois and worked to create DeWitt County arranging for his brother, Kersey H. Fell, to become the clerk responsible for organizing the new county. He established Livingston County, which he named, and backed the founders of Pontiac, Illinois, which he also named. Fell invested in lands in Bloomington, Chicago, Milwaukee, Danville, and other places in central and eastern Illinois.