Question: The society that operates the Mayflower House Museum was founded in what year?

Context articles: Hill–Physick–Keith House
Warden's House Museum
Salisbury Mansion and Store
Riley Lucas Bartholomew House
William Tanner House Museum
The Mayflower Society
Mayflower House Museum
Colbert House (Ilwaco, Washington)
Ashbel Woodward House
John A. North House

The Hill–Physick–Keith House, also known as the Hill–Keith–Physick House, the Hill–Physick House, or simply the Physick House, is a historic house museum located at 321 S. 4th Street in the Society Hill neighborhood of Philadelphia, Pennsylvania, USA.
 Built 1786, it was the home of Philip Syng Physick (1768-1837), who has been called "the father of American surgery".
 The house was declared a National Historic Landmark in 1976.
 It is now owned and operated by the Philadelphia Society for the Presevation of Landmarks as a house museum.
The Warden's House Museum is a historic house museum in Stillwater, Minnesota, United States.
 From 1853 to 1914 it was the official residence for the wardens of the Minnesota Territorial Prison, which became the Minnesota State Prison upon statehood in 1858.
 The Washington County Historical Society has operated the house since 1941, making it the second-oldest house museum in Minnesota.
 It was listed on the National Register of Historic Places in 1974 as the Minnesota Territorial/State Prison Warden's House for having state-level significance in the themes of architecture and social history.
 It was nominated for being the only surviving structure of the prison's Minnesota Territory period and the chief remnant of its statehood years.
The Salisbury Mansion and Store is an historic house museum at 40 Highland Street in Worcester, Massachusetts.
 The house was originally built on Lincoln Square in 1772 by Stephen Salisbury I with an attached storehouse from which he sold imported goods under the name "S. & S. Salisbury".
 He and his brother Samuel had originally been in business together selling hardware goods in Boston, and Stephen moved to Worcester to expand the operation.
 In 1820 the store was closed down, and the space was converted for residential use by the family, which occupied it until 1851.
 Thereafter it served as a girls' school, tenant house, and then a gentleman's social club until 1929, when the building was threatened with demolition by the then occupants, the Worcester Lincoln Square Boys Club, who wanted to build more modern premises.
 It was saved by local efforts and moved to its current location on the former Salisbury estate near the museum and next to Salisbury House.
 It was donated to the American Antiquarian Society, which promptly gave it to the Worcester Art Museum, both of which were founded by Stephen Salisbury III.
 The museum undertook to restore the much-altered building to its condition as of 1830, and opened it for group tours as a historic house museum.
The Riley Lucas Bartholomew House is a historic house museum in Richfield, Minnesota, United States, originally the home of prominent early Minnesotan Riley Bartholomew (1807–1894).
 The Richfield Historical Society operates the house as the Bartholomew House Museum adjacent to their Richfield History Center.
The William Tanner House Museum, also known as the William A. Tanner House, is a historic residence and museum in Aurora, Illinois.
 It was built in 1857 for William A. Tanner, a hardware merchant.
 His descendants lived in the house until it was donated to the Aurora Historical Society in 1936.
 It now operates as a Victorian-period historic house museum.
The General Society of "Mayflower" Descendants — commonly called the Mayflower Society — is a hereditary organization of individuals who have documented their descent from one or more of the 102 passengers who arrived on the "Mayflower" in 1620 at what is now Plymouth, Massachusetts.
 The Society was founded at Plymouth in 1897.
The Mayflower House Museum is an 18th-century period historic house museum in Plymouth, Massachusetts operated by The Mayflower Society, also known as the General Society of "Mayflower" Descendants.
 The Society purchased the Edward Winslow House in 1941.
The Colbert House is a historic house museum owned by Washington State Parks and located in Ilwaco, Washington, at the corner of Spruce and Quaker streets.
 The house was originally built in 1872 and was moved to its current site in 1883.
 The house was owned by a fishing family and was restored in 1994 to a late 19th-century appearance with Colbert family furnishings and decorative items.
 Following its restoration, the house was operated by Cape Disappointment State Park as a historic house museum that was open by appointment only.
 In 2009, the Long Beach Area Parks Management Plan deemed the operation of the building as a house museum to be "not feasible at this time" and that "State Parks will preserve the building until such time as a feasible and sustainable use becomes apparent."
The Ashbel Woodward House is a historic house museum at 387 Connecticut Route 32 in Franklin, Connecticut.
 The house is now operated by the Town of Franklin as the Dr. Ashbel Woodward House Museum.
 It is a 2-1/2 story wood frame structure, five bays wide, with a side gable roof, clapboard siding, a granite foundation, and a pair of brick chimneys.
 The museum features exhibits on local history and an art gallery.
 The main entrance is centered on the front, slightly recessed under a Greek Revival surround with pilasters and entablature.
 The building corners are also pilastered, and the side gable ends have semi-elliptical windows.
 An ell, apparently original as it shares the foundation with the house, extends to the rear.
 The property also includes two barns and a third outbuilding that probably functioned as a corn crib.
 The house was built c. 1835, and is a fine local example of a Greek Revival house in a rural setting.
 It was home for many years to Ashbel Woodward, a local doctor.
 His descendants gave the property to the state in 1947.
 The house is now owned by the town, whose historical society operates it as a local history museum.
The John A. North House is a historic house museum and archives located in Lewisburg, Greenbrier County, West Virginia.
 Currently, the North House is Greenbrier County's only historic house museum.
 Since 1976, The Greenbrier Historical Society has operated within the North House, and in 1992 the North House was officially purchased by the Greenbrier Historical Society.
 In 1992, the home officially became known as " North House Museum, Greenbrier Historical Society."