William Penn (October 14, 1644 – July 30, 1718) is an English real estate entrepreneur, philosopher, and founder and "absolute proprietor" of the Province of Pennsylvania, the English North American colony and the future U. S. State of Pennsylvania.

He is an early champion of democracy and religious freedom, notable for his good relations and successful treaties with the Lenape Indians.

Under his direction, the city of Philadelphia is planned and developed.

In 1682, James Duke of York, the future James II of England, hands over a large piece of his American holdings to William Penn.

This land includes present-day Pennsylvania and Delaware.

Penn immediately sails to America and his first step on American soil took takes place in New Castle in 1682.

On this occasion, the colonists pledge allegiance to Penn as their new Proprietor, and the first general assembly is held in the colony.

Afterwards, Penn journeys upriver and founds Philadelphia.

However, Penn's Quaker government is not viewed favorably by the Dutch, Swedish, and English settlers in what is now today's Delaware.

They have no "historical" allegiance to Pennsylvania, so they, almost immediately, begin petitioning for their own Assembly.

In 1704 they achieve their goal when the three southernmost counties of Pennsylvania are permitted to split off and become the new semi-autonomous colony of lower Delaware.

As the most prominent, prosperous and influential "city" in the new colony, New Castle becomes the capital.

As one of the earlier supporters of colonial unification, Penn writes and urges for a Union of all the English colonies in what is to become the United States of America.

The democratic principles that he sets forth in the Pennsylvania Frame of Government serve as an inspiration for the United States Constitution.

As a pacifist Quaker, Penn considers the problems of war and peace deeply, and includes a plan for a United States of Europe, "European Dyet, Parliament or Estates," in his voluminous writings.