Benjamin Franklin established himself as a Philadelphia printer after working in Boston and London. He acquired the Pennsylvania Gazette in 1729 and published Poor Richard's Almanack from 1733. The newspaper, almanac, and printing business brought income and a broad readership. His Junto discussion group encouraged practical schemes for improvement, and he helped organize the Library Company, a fire company, Pennsylvania Hospital, and the academy that developed into the University of Pennsylvania.

Financial independence allowed Franklin to devote more time to science and public service. His electrical experiments established an international reputation and helped demonstrate the relationship between lightning and electricity. The lightning rod translated this work into a practical protective device. His other inventions and investigations also sought to make knowledge useful. Scientific recognition also enhanced his standing abroad.

Franklin served in Pennsylvania's assembly and in the postal administration. At the Albany Congress in 1754 he proposed a plan for colonial union that was adopted by the delegates but rejected by the colonies. As Pennsylvania's agent in London during 1757–1762 and 1764–1775, he sought changes in provincial government and defended colonial interests. His testimony during the Stamp Act controversy helped the case for repeal, but growing conflict with British officials eventually made reconciliation untenable.

Returning to Philadelphia in 1775, he joined the Continental Congress and served on the committee that drafted the Declaration of Independence. Sent to France in 1776, he used diplomacy and his public reputation to help secure the treaties of alliance and commerce in 1778. French assistance was crucial to the American war effort. With John Adams and John Jay, he helped negotiate the Treaty of Paris in 1783, obtaining British recognition of United States independence.

After returning home in 1785, Franklin headed Pennsylvania's executive council and participated in the Constitutional Convention of 1787, encouraging compromise despite his reservations. His late opposition to slavery represented a change from earlier slaveholding and the publication of slave-sale advertisements. As president of the Pennsylvania abolition society, he signed its 1790 petition to Congress. He died that April, leaving a career that connected publishing, experimental science, civic organization, and the creation of a new republic.