Penn, William, an eminent writer amongst the Quakers, and the planter and legislator of Pennsylvania, was the son of Sir William Penn, and born at London in the year 1644. In 1660 he was entered a gentleman of Christ-Church, in Oxford; but having previously received an impression from the preaching of one Thomas Lee, a Quaker, he withdrew, with some other students, from the national worship, and held private meetings, where they preached and prayed amongst themselves. This having given great offence to the heads of the college, Mr Penn, although only sixteen years of age, was fined for non-conformity; and, continuing his religious exercises, he was at length expelled the college. Upon his return home, he was on the same account treated with great severity by his father, who at length turned him out of doors; but his resentment afterwards abating, Penn was sent, in company with some persons of quality, to France, where he continued for a considerable time, and returned not only well skilled in the French language, but a polite and accomplished gentleman. About the year 1666, his father committed to his care a considerable estate in Ireland. Being found in one of the Quakers' meetings in Cork, he, with many others, was thrown into prison; but having written to the Earl of Orrery, he was soon after discharged. However, his father being informed that he still adhered to his opinions, sent for him to England, and finding him unmoved by all his arguments, turned him out of doors a second time. About the year 1668, he became a public preacher amongst the Quakers, and in that year was committed close prisoner to the Tower, where he wrote several treatises. Being discharged after seven months' imprisonment, he went to Ireland, where he also preached amongst the Quakers. Returning to England, he was, in 1670, committed to Newgate for preaching in Gracechurch Street meeting-house, London; but being tried at the sessions-house of the Old Bailey, he was acquitted. In September the same year his father died, and, being perfectly reconciled to his son, left him both his paternal blessing and a good estate. But his persecutions were not yet at an end; for in the year 1671 he was committed to Newgate, for preaching at a meeting in Wheeler Street, London; and during his imprisonment, which continued six months, he also wrote several treatises. After his discharge he went into Holland and Germany; and, in the beginning of the year 1672, married and settled with his family at Rickmansworth, in Hertfordshire. The same year he published several pieces, and particularly one against Reeve and Muggleton. In 1677 he again travelled into Holland and Germany, in order to propagate his opinions, and had frequent conversations with the Princess Elizabeth, daughter to the Queen of Bohemia, and sister to the Princess Sophia, mother of George I. In the year 1681, Charles II., in consideration of the services of Mr Penn's father, and several debts due to him by the crown at the time of his decease, granted Mr Penn and his heirs the province lying on the western side of the river Delaware, in North America, which thence obtained the name of Pennsylvania. Upon this Mr Penn published a brief account of the province, together with the king's patent; and proposing an easy purchase of lands, and good terms of settlement, for such as were inclined to remove thither, he induced many to proceed to the new settlement. These having made and improved their plantations to good advantage, the governor, in order to secure the planters from the native Indians, appointed commissioners to purchase the land which he had received from the king of the native Indians, and concluded a peace with them. The city of Philadelphia was planned and built; and he himself drew up the fundamental constitutions of Pennsylvania, in twenty-four articles. In 1681 he was elected a member of the Royal Society; and the next year he embarked for Pennsylvania, where he continued about two years, and returned to England in August 1684. Upon the accession of James II. to the throne, he was taken into a great degree of favour with his majesty, which exposed him to the imputation of being a Papist; but from this he fully vindicated himself. However, upon the Revolution, he was examined before the council in 1688, and obliged to give security for his appearance upon the first day of next term, which was afterwards continued. He was several times examined and discharged; and at length warrants being issued out against him, he was obliged to conceal himself during two or three years. But being at last permitted to appear before the king and council, he represented his innocence so effectually that he was acquitted. In August 1699, he, with his wife and family, embarked for Pennsylvania, whence he returned in 1701, in order to vindicate his proprietary right, which had been attacked during his absence. On Queen Anne's accession to the crown, he was in great favour with her majesty, and often at court. But in 1707 he was involved in a law-suit with the executors of a person who had formerly been his steward; and, though many thought him aggrieved, the Court of Chancery did not deem it proper to afford him any relief; upon which account he was obliged to live within the rules of the Fleet for several months, till the matter in dispute was accommodated. Penn died in the year 1718.

At one period of his life Penn lodged in a house in Norfolk Street, in the Strand. In the entrance to it he had a peeping-hole, through which he could see any person who came to him. A creditor one day sent in his name, and having been made to wait more than a reasonable time, he knocked for the servant, whom he asked, "Will not thy master see me?" "Friend," answered the servant, "he has seen thee, but he does not like thee." Mr Penn's friendly and pacific manner of treating the Indians produced in them an extraordinary love for him and his people; so that they maintained a perfect amity with the English settled in Pennsylvania. He was the great bulwark of the Quakers, in defence of whom he wrote numberless pieces. The most esteemed of these are, 1. His Primitive Christianity revived; 2. His defense of a paper entitled Gospel Truths, against the exceptions of the Bishop of Cork; 3. His Persuasive to Moderation; 4. His Good Advice to the Church of England, Roman Catholic, and Protestant Dissenter; 5. The Sandy Pennant. Foundation shaken; 6. No Cross, no Crown; 7. The great case of Liberty of Conscience debated; 8. The Christian Quaker and his Testimony stated and vindicated; 9. A Discourse of the general Rule of Faith and Practice, and Judge of Controversy; 10. England's Present Interest considered; 11. An Address to Protestants; 12. His Reflections and Maxims; 13. His Advice to his Children; 14. His Rise and Progress of the People called Quakers; 15. A Treatise on Oaths. Most of these have passed through several editions, some of them many. The letters between William Penn and Dr Tillotson, and William Penn and William Popple, together with Penn's letters to the Princess Elizabeth of the Rhine, and the Countess of Hornes, as also one to his wife on his going to Pennsylvania, are inserted in his works, which were first collected and published in two volumes folio; and the parts since selected, and abridged into one volume folio, are deservedly admired for the good sense by which they are characterized.