William Peters (1702- September 8, 1789) was an English lawyer and amateur architect from Liverpool who lived in Philadelphia for nearly three decades before returning to England. He built Belmont Mansion, one of the earliest villa-retreats on the banks of the Schuylkill River, and laid out formal gardens there.
Peters arrived in Pennsylvania in 1739 and embarked on a lucrative private law practice. Guided by his taste for luxury and his pretensions to high social status, he purchased, in July 1742, a 220-acre parcel of land on a commanding position on the west side of the Schuylkill, which he named Belmont.  He immediately began to develop the property in a remarkably ambitious and sophisticated manner. Conceiving of Belmont as an Epicurean retreat, he designed a Palladian-style villa (only the second in America) and extensive pleasure gardens.  Belmont evidently established Peters’s reputation as an amateur gentleman-architect and he was often called upon to provide his Philadelphia neighbors with expertise in architectural matters. In 1743, while mulling plans for a new residence at Springettsbury, his country estate on the opposite side of the river from Belmont, Thomas Penn, the Proprietor of Pennsylvania, informed Peters, “I hope to have the pleasure ere long of visiting your Country Retirement and gaining something by your experience.”  Writing to Penn a few years later, the Philadelphia merchant Richard Hockley praised the plan Peters had drawn up for a townhouse as “a very compleat one, of the dimensions, and the best I think by far in this place and most convenient and commodious.”  Peters went on to supervise the construction of a ferry house on the Delaware River for Penn, and to advise Benjamin Chew on plans for a country house he intended to build in the Germantown neighborhood near Philadelphia. 
Peters’s introduction to the Penn family came through his younger brother, the Anglican Rev. Richard Peters (1704 – 1776), who had immigrated to Philadelphia in 1735 and secured Thomas Penn’s patronage soon after. William Peters provided legal services to the Penns and through their agency gained appointments to a number of profitable public offices, including Notary Public for Pennsylvania (1744), Register of the Admiralty Court of Pennsylvania (1744), and Justice of the Peace and of the Courts of Common Pleas, Quarter Sessions, and Orphans. (1757)  Over the years, Thomas Penn became concerned by the degree to which building and landscaping projects at Belmont were distracting Peters from his official duties. In 1752 Rev. Peters felt obliged to apologize for his brother’s extravagant expenditure of capital and attention at Belmont, acknowledging in a letter to Penn that William’s “country schemes had well night ruined him, & [the] hurt done to his circumstances by their expense was not half so great as that done by a dissipation of mind.” He nevertheless assured Penn that “now he is come to town & in full business I am in hopes he will do much good.”  Despite this reassurance, William Peters continued to devote himself to rural retirement at Belmont while neglecting his business in town, prompting Penn, in a letter of 1760, to make the pointed observation, “He may, I think fix some office hours, so as to have time for his Air, Exercise and Retirement.”  Penn allowed William Peters to succeed his brother Richard as secretary of the Pennsylvania Land Office in 1760. Peters served in that capacity for five years, using his position to supplement his income and expand his property holdings by raising warrant and patent fees and purchasing land under false names.  This self-dealing led to a final rift with Penn, who dismissed Peters from office in 1765. Peters returned to England in 1768, settling in Knutsford, Cheshire.  He created a deed of trust leaving Belmont in the care of his eldest son, Richard Peters, to whom he legally transferred the estate and all his other Pennsylvania properties in 1786.  Peters continued to pursue his interest in horticulture after returning to England. In his 84th year, he sent parcels of flower seeds to his son and daughter in Philadelphia, informing them in a letter of January 8, 1787: “The seeds consist of an amazing variety of sorts, and if you are as fond of flowers as I am, they will afford you a great deal of pleasure and I shall be glad to hear from you how they succeed.” 
- "...went to William Peters's house having some acquaintance with his wife. She was at home and with her daughter Polly received us kindly in one wing of the house. After a while passed through a covered passage to the large hall, well furnished, the top adorned with instruments of music, coats of arms, crests and other ornaments in stucco, its sides by paintings and statues in bronze. From the front of this hall you have a prospect bounded by the Jerseys like a blue ridge. A broad walk of English Cherry trees leads down to the river. The doors of the house opening opposite admit a prospect of the length of the garden over a broad gravel walk to a large handsome summer house on a green. From the windows a vista is terminated by an obelisk. On the right you enter a labyrinth of hedge of low cedar and spruce. In the middle stands a statue of Apollo. In the garden are statues of Diana, Fame and Mercury with urns. We left the garden for a wood cut into vistas. In the midst is a Chinese temple for a summer house. One avenue gives a fine prospect of the City. With a spy glass you discern the houses and hospital distinctly. Another avenue looks to the obelisk."
- Richard Peters, Jr., “Belmont Mansion,” Proceedings of the Numismatic and Antiquarian Society of Philadelphia, 30 (1925): 78-79, view on Zotero.
- Mark Reinberger, “Belmont: The Bourgeois Villa in Eighteenth-Century Philadelphia,” Arris: Journal of the Southeast Chapter of the Society of Architectural Historians, 9 (1998): 23, view on Zotero.
- Thomas Penn to William Peters, August 22, 1743, quoted in Reinberger, 1998: 17. view on Zotero. For the involvement of “Mr. Peters” in Penn’s plans for a projected residence at Springettsbury, see Richard Hockley to Thomas Penn, June 27, 1742 in Richard Hockley, "Selected Letters from the Letter-Book of Richard Hockley, of Philadelphia, 1739-1742 (Continued)," The Pennsylvania Magazine of History and Biography, 27 (1903): 435, view on Zotero.
- Richard Hockley to Thomas Penn, April 18, 1749, quoted in Reinberger, 1998, 18, view on Zotero.
- Reinberger, 1998: 18, view on Zotero.
- John Hill Martin, Martin’s Bench and Bar of Philadelphia: Together with Other Lists of Persons Appointed to Administer the Laws in the City and County of Philadelphia, and the Province and Commonwealth of Pennsylvania (Philadelphia: Res Welsh & Co., Publishers, 1883), 9, 33-34, 45, view on Zotero.
- The Rev. Richard Peters to Thomas Penn, June 20, 1752, quoted in Reinberger, 36, 1998, n.17, view on Zotero.
- Thomas Penn to the Rev. Richard Peters, November 15, 1760, quoted in Reinberger, 1998: 27, view on Zotero.
- Donna B. Munger, Pennsylvania Land Records: A History and Guide for Research (Wilmington, Del.: Scholarly Resources, Inc., 1991) 96, view on Zotero.
- John W. Jordan, ed., Colonial Families of Philadelphia, 2 vols. (New York and Chicago: The Lewis Publishing Company, 1911), 2: 1107, view on Zotero.
- Nellie Peters Black, Richard Peters, His Ancestors and Descendents: 1810-1889 (Atlanta: Foote & Davies, 1904), 61, 91, view on Zotero.
- Nellie Peters Black, Richard Peters, His Ancestors and Descendents: 1810-1889 (Atlanta: Foote & Davies, 1904), 36, view on Zotero.
- George Vaux, "Extracts from the Diary of Hannah Callender," Pennsylvania Magazine of History and Biography, 12 (1888), view on Zotero.