Question: As of 2010, how many people lived in the region in which Robert Sheffey was a preacher to?

Context paragraphs:
Coplay, Pennsylvania: Coplay is a borough in Lehigh County, Pennsylvania, six miles (10 km) northwest of Allentown.  It is part of the Lehigh Valley region of the state.  In 1900, 1,581 people lived in Coplay; in 1910, 2,670 people lived there.  The population was 3,387 at the 2000 census.  Coplay is included in the Allentown-Bethlehem-Easton, PA-NJ Metropolitan Statistical Area, which is also included in the New York City-Newark, New Jersey, NY-NJ-CT-PA Combined Statistical Area.

Robert Sheffey: Robert Sayers Sheffey (July 4, 1820 – August 30, 1902) was a Methodist evangelist and circuit-riding preacher, renowned for his eccentricities and power in prayer, who ministered to, and became part of the folklore of, the Appalachian region of southwest Virginia, southern West Virginia and eastern Tennessee.

Munhall, Pennsylvania: Munhall is a borough in Allegheny County, Pennsylvania, on the west bank of the Monongahela River, 8 mi south of the confluence of the Monongahela and the Allegheny rivers where the Ohio River begins.  It abuts the borough of Homestead.  A large part of the Homestead Works of the Carnegie Steel Company existed in Munhall.  Steel products were the only items made in Munhall in 1910 when 5,185 people lived here.  In 1940, 13,900 people lived in Munhall.  The population was 11,406 at the 2010 census.  Munhall, along with the boroughs of Homestead and West Homestead, are served by the Steel Valley School District.

Sayre, Pennsylvania: Sayre is the largest borough in Bradford County, Pennsylvania, 18 mi southeast of Elmira, New York.  In the past, various iron products were made there.  In 1900, 5,243 people lived there; in 1910, 6,426 people lived there, and in 1940, 7,569 persons made their homes in Sayre.  The population was 5,587 at the 2010 census.

Appalachia: Appalachia ( ) is a cultural region in the Eastern United States that stretches from the Southern Tier of New York to northern Alabama, Mississippi and Georgia.  While the Appalachian Mountains stretch from Belle Isle (Newfoundland and Labrador) in Canada to Cheaha Mountain in Alabama, the cultural region of Appalachia typically refers only to the central and southern portions of the range.  As of the 2010 United States Census, the region was home to approximately 25 million people.

Piute Pass Archeological District: The Piute Pass Archeological District is an archaeological district located along Piute Creek in eastern San Bernardino County, California.  The district encompasses the area around the historic Fort Piute and includes a variety of prehistoric and historic resources.  The Piute Pass area was inhabited by several Native American tribes dating back to the middle Holocene epoch.  The Patayan people lived in the area during the late prehistoric period, while the Chemehuevi people lived there after the Patayan and through the early historic period.  Both groups left petroglyphs in the area, and remains of Chemehuevi habitation sites have also been discovered.  After European settlers came to the region, the pass became the site of Fort Piute, a U.S. Army redoubt which protected travelers along the Mojave Road.

West Hazleton, Pennsylvania: West Hazleton is a borough in Luzerne County, Pennsylvania, 31 mi south of Wilkes Barre.  In 1900, 2,516 people lived here; in 1910, 4,715 people lived here.  The population was 4,594 at the 2010 census.  This represents a 29.7% increase in population from the 2000 census count of 3,542.

List of Ottoman people: List of Ottoman people refers to people lived in the Ottoman Empire (1299-1922).  Naturally, some people lived in the last years of the empire also lived in the early years of Turkey or other countries controlled by the Ottoman Empire.

Mercersburg, Pennsylvania: Mercersburg is a borough in Franklin County, Pennsylvania, United States.  It is 72 mi southwest of Harrisburg, the state capital.  Originally called "Black Town", it was incorporated in 1831.  In 1900, 956 people lived here, and in 1910, 1,410 people lived here.  The population was 1,561 at the 2010 census.

Sharpsburg, Pennsylvania: Sharpsburg is a borough in Allegheny County, Pennsylvania, 5 mi northeast of downtown Pittsburgh, along the Allegheny River.  In the past, it had a rolling mill, foundries, machine shops, and manufacturers of varnish, brick, glass, lumber products, wire, hair, felt, and lubricating oil.  In 1900, 6,842 people lived here; by 1940, 8,202 people lived in Sharpsburg.  The population was 3,446 at the 2010 census.

Supporting paragraphs: Robert Sheffey Appalachia
Answer: 25 million people