Rockdale, also known as The Robinson/Stirling Place, is a historic home and farm complex located at Fallston, Harford County, Maryland, United States.
 It is a farm developed from the late 18th century through the early 20th century.
 The dwelling is in three parts.
 The east room of the east wing is the earliest section dating from the 18th century.
 The largest or main portion of the dwelling dates from between 1815 and 1830.
 The north wing, a bay centered in the south façade of the second story, and a small conservatory, date from the very early 20th century.
 The main house is five bays in length, two and a half stories, of stone construction, stuccoed and scored.
 The home is surrounded by several outbuildings, trees, and other plantings, and the remains of formal gardens and garden structures developed in the early 20th century.
 It was the residence of William E. Robinson (1860-1935), an entrepreneur in the local canning industry.
The Grace Street Commercial Historic District is a national historic district located in Richmond, Virginia.
 The district encompasses 93 contributing buildings located in downtown Richmond.
 The buildings reflect the core of the city's early 20th century retail development and the remnants of a 19th-century residential neighborhood.
 The buildings are in a variety of popular 19th century and early 20th century architectural styles including Classical Revival, Mission Revival, International Style, and Colonial Revival.
 Notable buildings include the Administration and Equipment Building for the Chesapeake & Potomac Telephone Company (1929), Thalhimer's Department Store, Atlantic Life Building (1950-1959), Miller & Rhoads Department Store, Berry-Burk Building, former W. W. Foster Studios (1927), Bank of Virginia (1949), Investment Realty Company building (1930), W.T. Grant Store (1939), Hotel John Marshall (1927), Franklin Federal Savings and Loan building (1954), and the Tompkins House (1820).
 Located in the district and separately listed are the Loew's Theatre, Centenary United Methodist Church, Joseph P. Winston House, Central National Bank, and National Theater.
Cecil James Sharp (22 November 1859 – 23 June 1924) was the founding father of the folk-song revival in England in the early 20th century.
Ecology is a new science and considered as an important branch of biological science, having only become prominent during the second half of the 20th century.
 Ecological thought is derivative of established currents in philosophy, particularly from ethics and politics.
 Its history stems all the way back to the 4th century.
 One of the first ecologists whose writings survive may have been Aristotle or perhaps his student, Theophrastus, both of whom had interest in many species of animals and plants.
 Theophrastus described interrelationships between animals and their environment as early as the 4th century BC.
 Ecology developed substantially in the 18th and 19th century.
 It began with Carl Linnaeus and his work with the economy of nature.
 Soon after came Alexander von Humboldt and his work with botanical geography.
 Alfred Russel Wallace and Karl Möbius then contributed with the notion of biocoenosis.
 Eugenius Warming’s work with ecological plant geography led to the founding of ecology as a discipline.
 Charles Darwin’s work also contributed to the science of ecology, and Darwin is often attributed with progressing the discipline more than anyone else in its young history.
 Ecological thought expanded even more in the early 20th century.
 Major contributions included: Eduard Suess’ and Vladimir Vernadsky’s work with the biosphere, Arthur Tansley’s ecosystem, Charles Elton's "Animal Ecology", and Henry Cowles ecological succession.
 Ecology influenced the social sciences and humanities.
 Human ecology began in the early 20th century and it recognized humans as an ecological factor.
 Later James Lovelock advanced views on earth as a macro-organism with the Gaia hypothesis.
 Conservation stemmed from the science of ecology.
 Important figures and movements include Shelford and the ESA, National Environmental Policy act, George Perkins Marsh, Theodore Roosevelt, Stephen A. Forbes, and post-Dust Bowl conservation.
 Later in the 20th century world governments collaborated on man’s effects on the biosphere and Earth’s environment.
Yalecrest is a residential neighborhood located on the East Bench of Salt Lake City and is known for the architectural variety and rare collection of turn-of-the-century homes – all within a six block radius bordered by the South Side of Sunnyside Avenue, North Side of 1300 South, East Side of 1300 East and West Side of 1900 East.
 Yalecrest is commonly referred to as the renowned “Harvard-Yale area” and many streets are named after Ivy League or major U.S. universities.
 It is a remarkably visually cohesive area with uniform setbacks, historic houses of the same era with comparable massing and landscaping, as well as streets lined with mature shade trees, and a surprising level of contributing structures that retain their historic integrity.
 Yalecrest contains 1,487 homes that were built in the early 20th century starting as early as 1912 with the vast majority (74%) built during the period of 1920-1940.
 The remaining homes in the Eastern Most part of the neighborhood were built during the post war boom.
 Yalecrest has the largest concentration of period revival English Cottages, English Tudors, French Norman and Spanish Colonial homes anywhere in Utah.
 These houses exhibit a variety of period revival styles with the largest portion being English Tudor and English Cottage.
 According to the Salt Lake City Planning Department, the architectural variety and concentration of period cottages found in Yalecrest are “unrivalled in the state.”
 Examples from Yalecrest are used to illustrate period revival cottages styles in the only statewide architectural style manual.
 There are 22 subdivisions which were platted and built by the prominent architects and developers of the day responsible for early 20th Century east side Salt Lake City development.
 .
 Yalecrest has been on the National Register of Historic Places since November 8, 2007.
 One home in the neighborhood, the George Albert Smith home at 1302 Yale Avenue, is listed on the National Register since 1993.
Esther Blaikie MacKinnon (1885–1934) was a Scottish artist, who was known for her paintings and engravings.
 During her career, MacKinnon worked with a variety of media including paint, dry point, etchings, and black and white drawings.
 Notable were her portraits of Cecil and Evelyn Sharp, which currently are part of The National Portrait Gallery's primary collection.
 Her work was exhibited at the Royal Scottish Academy, the Royal Glasgow Institute, the Royal Academy, and the Society of Women Artists within her lifetime.
Lucy Etheldred Broadwood (9 August 1858 – 22 August 1929) was an English folksong collector and researcher during the late 19th and early 20th centuries.
 As one of the founder members of the Folk-Song Society and Editor of the Folk Song Journal, she was one of the main influences of the English folk revival of that period.
 She was an accomplished singer, composer, piano accompanist, and amateur poet.
 She was much sought after as a song and choral singing adjudicator at music festivals throughout England, and was also one of the founders of the Leith Hill Music Festival in Surrey.
Encarnación de Díaz is a town and municipality located in the far northeast of the state of Jalisco in north central Mexico.
 It is located in a natural pass that connects the Los Altos region of Jalisco to points north, and from pre Hispanic times until the 20th century, it was a major thoroughfare for north-south travel.
 The town began as a way station along a road built through this pass in the 17th century, formally becoming a town in 1760.
 It began to function as a municipality in the latter 19th century, but this status was not confirmed until the early 20th.
 Transport, along with numerous prosperous haciendas supported the economy of the area until the early 20th century, when travel patterns and the Mexican Revolution spurred its decline.
 In the 1920s, it was a center of rebellion during the Cristero War, and the town contains Mexico’s only museum exclusively dedicated to this episode in history.
 It also contains a museum dedicated to various naturally occurring mummies which have been found in the municipal cemetery.
Loudon Road Historic District is a national historic district located at Loudonville in Albany County, New York.
 It includes 20 contributing buildings; 17 are residences and three are in commercial use.
 The district encompasses representative structures from the areas growth during the 19th and early 20th century.
 Notable structures include the home of Elias Ireland (ca. 1820), an early school from 1811 that was rebuilt about 1850, summer cottages from the late 19th century including that of Judge Ira Harris, and Georgian Revival homes from the early 20th century.
Come all you worthy gentlemen, sometimes referred to as the Somerset Carol, is an English folk carol of unknown authorship.
 It was collected from a Mr. Rapsey, of Bridgwater during the English Folk-song revival at the turn of the 20th century by Cecil Sharp.
 It was first published in 1905 in Sharp and Marson's "Folk songs from Somerset".

Question: Who was a founding father of the folk-song revival in England in the early 20th century and had a portait painted of them by Esther Blaikie MacKinnon?
Answer: Cecil James Sharp