|Borough of Eddystone|
|Elevation||20 ft (6.1 m)|
|Area||1.5 sq mi (3.9 km2)|
|- land||1.0 sq mi (3 km2)|
|- water||0.5 sq mi (1 km2), 33.33%|
|Density||2,352.6 / sq mi (908.3 / km2)|
|- summer (DST)||EDT (UTC-4)|
The area at the mouth of Ridley Creek was first called "Tequirassy" by Native Americans. The land was owned by Olof Persson Stille, one of the early settlers from New Sweden, who had immigrated in 1641. Olof Stille, a millwright by trade, came from Penningby Manor in Länna in the county of Uppland, north of Stockholm, Sweden. After the conquest of the colony by the Dutch in 1658, Stille was one of the four commissaries or magistrates appointed to administer justice among the inhabitants, and thus became a judge of the first court on the banks of the Delaware.
The Borough of Eddystone was formed around the Eddystone Print Works. William Simpson & Sons established the Eddystone Print Works on the land that is now Eddystone in October 1873, after the land on which their previous factory had operated was condemned to make way for Fairmount Park.
Eddystone Borough was incorporated on December 7, 1888. Eddystone's petition for incorporation was challenged in court on several grounds, including that "the finances of the township of Ridley and of the Ridley school district will be diminished by the creation of this borough."  On December 3, 1888, the Delaware County Court of Common Pleas issued an opinion rejecting these claims, noting that while Ridley's "revenues...will be diminished, so will its burdens." 
Children in Eddystone attend school at the Eddystone Elementary School on 9th street. The Elementary school is located on the site of the old Eddystone High School, which burned down in 1960. After children pass the 5th grade, they move onto Ridley Middle School, a part of the Ridley School District.
Eddystone is located at (39.859345, -75.340920).
According to the United States Census Bureau, the borough has a total area of 1.5 square miles (3.9 km2), of which, 1.0 square mile (2.6 km2) of it is land and 0.5 square miles (1.3 km2) of it (30.67%) is water.
Eddystone gets its name from William Simpson who was so impressed by the Eddystone Lighthouse on a visit to England that he named the town & print works he'd founded after it.
As of the census of 2000, there were 2,442 people, 964 households, and 607 families residing in the borough. The population density was 2,352.6 people per square mile (906.6/km²). There were 1,035 housing units at an average density of 997.1 per square mile (384.2/km²). The racial makeup of the borough was 95.45% White, 1.76% African American, 0.33% Native American, 0.49% Asian, 0.61% from other races, and 1.35% from two or more races. Hispanic or Latino of any race were 1.84% of the population.
There were 964 households out of which 31.7% had children under the age of 18 living with them, 40.8% were married couples living together, 16.8% had a female householder with no husband present, and 37.0% were non-families. 32.5% of all households were made up of individuals and 14.2% had someone living alone who was 65 years of age or older. The average household size was 2.53 and the average family size was 3.24.
In the borough the population was spread out with 28.4% under the age of 18, 7.2% from 18 to 24, 29.7% from 25 to 44, 20.2% from 45 to 64, and 14.5% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 95.8 males. For every 100 females age 18 and over, there were 90.6 males.
The median income for a household in the borough was $37,543, and the median income for a family was $47,054. Males had a median income of $36,422 versus $25,069 for females. The per capita income for the borough was $16,537. About 11.6% of families and 12.1% of the population were below the poverty line, including 18.1% of those under age 18 and 16.4% of those age 65 or over.
In 2010 Eddystone had a population of 2410. Its ethnic and racial composition was 80.3% non-Hispanic white, 11.7% black or African American, 0.1% Native American, 1.3% Asian, 0.2% non-Hispanic of some other race, 3.2% reporting two or more races and 4.4% Hispanic or Latino.
Eddystone has a history of heavy industry. It was the site of the largest Baldwin Locomotive Works plant (the smaller being in Spring Garden, Philadelphia). Baldwin was once the largest manufacturer of steam locomotives in the world. Today an Exelon generating station occupies some of the riverfront. The Platt-LePage Aircraft Company built some of the earliest rotorcraft on adjacent land to the northeast (outside the borough). The site's association with military helicopters continued through McDonnell Aircraft and McDonnell Douglas all the way to the present, as a Boeing Integrated Defense Systems plant now operates there.
During World War I, Remington Arms opened the Eddystone Rifle Plant on Baldwin land with Baldwin management. Here it produced the Pattern 1914 Enfield rifle and M1917 Enfield rifle. A large portion of the rifles used by American soldiers in France in World War I were made at Eddystone. In January 1918 Remington Arms was absorbed by Midvale Steel and Ordnance Company, which took over the rifle plant.
Baldwin also formed a subsidiary company (Eddystone Ammunition Corporation) in 1915 to build artillery shells (Russian-model on British order).
On 10 April 1917, 133 people were killed in an explosion at the artillery shell plant. A monument near the Edgmont Avenue side of the Chester Rural Cemetery marks the final resting place for the remains of the unidentified victims, mostly women and young girls.
In 1917 the U.S. government also placed artillery shell orders, and bought out some of the assets of the Eddystone Ammunition Corporation. A new corporation, the similarly named Eddystone Munitions Company, was formed by Baldwin to make the shrapnel for the shells.
- History of Delaware County, Pennsylvania. (by Henry Graham Ashmead. Chapter LIV. Ridley Township. Philadelphia:L. H. Everts & Co.1884)
- Olof Persson Stille and his Family (by Dr. Peter Stebbins Craig. Swedish Colonial News,Volume 1, Number 16. Fall 1997) 
- Biographical and Historical Cyclopedia of Delaware County, Pennsylvania (by Samuel T. Wiley, Gresham Publishing Company New York 1894) p. 80
- The Awards and Claims of Exhibitors at the International Exhibition 1876 (National Association of Wool Manufacturers Boston) p. 138
- Biographical and Historical Cyclopedia of Delaware County, Pennsylvania (by Samuel T. Wiley, Gresham Publishing Company New York 1894) p. 123
- In re Eddystone Borough, 3 Delaware County Reports 541, 542 (1888)
- In re Eddystone Borough, 3 Delaware County Reports 541, 542 (1888).
- "US Gazetteer files: 2010, 2000, and 1990". United States Census Bureau. 2011-02-12. Retrieved 2011-04-23.
- "Census of Population and Housing". U.S. Census Bureau. Retrieved 11 December 2013.
- "American FactFinder". United States Census Bureau. Retrieved 2008-01-31.
- "Incorporated Places and Minor Civil Divisions Datasets: Subcounty Resident Population Estimates: April 1, 2010 to July 1, 2012". Population Estimates. U.S. Census Bureau. Retrieved 11 December 2013.
- 2010 census chart for Eddystone
- Westing 1966, p. 81.
- Westing 1966, pp. 80–81.
- Eddystone Disaster
- Westing 1966, p. 82.
- Westing, Frederick (1966), The locomotives that Baldwin built. Containing a complete facsimile of the original "History of the Baldwin Locomotive Works, 1831-1923", Crown Publishing Group, ISBN 978-0-517-36167-2, LCCN 66025422.