The town is near the location of Legionville, the training camp for General "Mad" Anthony Wayne's Legion of the United States. Wayne's was the first attempt to provide basic training for regular U.S. Army recruits and Legionville was the first facility established expressly for this purpose.
The Harmony Society first settled the area in the early 1800s, founding the village of "Ökonomie" or Economy in 1824. Although initially successful, accumulating significant landholdings, the sect went into decline. By the end of the nineteenth century only a few Harmonists remained. The Society was dissolved and its vast real estate holdings sold, much of it to the American Bridge Company, who subsequently enlarged the town and incorporated it as Ambridge in 1905.
American Bridge attracted thousands of immigrants who came to fulfill their dreams of work, freedom, and peace. The steel mills became the focal point of the town. Most of the employees were relatives of relatives and the small town grew, with wards separating the town into ethnic sections. The First street gang, the third ward crew, and the up towners... everyone had a nickname such as "Billy the Greek", "Luke the Cro", "Froggy", and "Scumpski".
With the growth of the steel mills, Ambridge became a world-wide leader in steel production. The borough became known for bridge building, metal molding, and the manufacture of tubes (large iron pipes). During World War II, numerous small vessels such as LSTs were constructed in Ambridge by the American Bridge Company. The area was also home to several other steel mills like Armco, the pipe mill who manufactured oil piping, and A.M. Byers, a major iron and tool fabricator. Eventually competition by foreign steel producers began to dwindle the share of the steel market for U.S. manufacturers. With the shift of steel production to areas overseas, the Ambridge Bridge Company ended operations in Ambridge in 1983. The legacy of American Bridge can be seen today from coast to coast, from the Golden Gate Bridge in San Francisco to the Brooklyn Bridge in New York.
Although the different ethnic groups of Ambridge have blended over time, the community continues to recognize the origins from which it came. Since 1966, Ambridge has held an annual heritage festival celebrating the borough's ethnic pride. Diversity in food, music, and entertainment continues to unite the community in remembering its origins. Organized by the Ambridge Chamber of Commerce, the three-day Nationality Days festival takes place in May and is located in the heart of the downtown Commercial District. Vendors line the center of Merchant Street as thousands of attendees – locals and tourists – enjoy Italian, Ukrainian, Greek, Polish, German, Croatian, and Slovenian cuisine. Booths are sponsored by numerous churches in Ambridge, bringing with them the recipes for their cultural dishes such as pirohy, haluski, stuffed cabbage, and borscht. Live entertainment, arts and crafts, and children's activities are also available.
With Ambridge now over 100 years old, revitalization is beginning to occur along Merchant Street in the Downtown Commercial District. Entrepreneurs and investors have begun to renovate the Victorian facades of the commercial storefronts. Antique shops are opening in the Historic District, which is also a National Historic Landmark, and a once industrial warehouse area is being converted to condominiums, shops, and parks. In 2007 Ambridge was designated as a Preserve America Community by the White House. Convenient to Pittsburgh along the Ohio River Boulevard and just across the Ohio River from the Pittsburgh Airport, Ambridge leaders hope it will benefit by its location and low cost of living.
According to the United States Census Bureau, the borough has a total area of 1.7 square miles (4.4 km²), of which, 1.5 square miles (3.8 km²) of it is land and 0.2 square miles (0.6 km²) of it (12.87%) is water.
There were 3,595 households out of which 23.2% had children under the age of 18 living with them, 32.6% were married couples living together, 16.9% had a female householder with no husband present, and 45.3% were non-families. 39.8% of all households were made up of individuals and 18.5% had someone living alone who was 65 years of age or older. The average household size was 2.14 and the average family size was 2.88.
In the borough the population was spread out with 21.7% under the age of 18, 7.9% from 18 to 24, 27.2% from 25 to 44, 20.2% from 45 to 64, and 23.0% who were 65 years of age or older. The median age was 40 years. For every 100 females there were 89.6 males. For every 100 females age 18 and over, there were 85.9 males.
The median income for a household in the borough was $26,263, and the median income for a family was $35,529. Males had a median income of $30,996 versus $21,455 for females. The per capita income for the borough was $15,089. About 16.4% of families and 17.8% of the population were below the poverty line, including 26.3% of those under age 18 and 14.1% of those age 65 or over.
The town's high school is Ambridge Area High School.
Students and citizens, are known by the locals as "Bridgers", which is also the name of the football team.Ambridge is also home to Trinity Episcopal School for Ministry, a seminary of the Episcopal Church in the United States of America.