Initially populated by Irish and Scottish immigrants, Butler saw a large influx of German settlers in the early 19th century.

It contributed to the Steel Belt manufacturing region as home to the Standard Steel Car Company, which produced early all-steel railcars, and the American Bantam Car Company, known for developing the original Willys Jeep.

After settling in Butler, the two brothers laid out the community by drawing up plots of land for more incoming settlers.

In 1802, the German immigrants began arriving, with Detmar Basse settling in Jackson Township in 1802 and founding Zelienople the following year.

John A. Roebling settled Saxonburg in 1832, by which time most of the county was filled with German settlers.

The steel workers of Butler made artillery and naval shells during World War II.

The site is now occupied by a vacant strip mall, as well as the Butler Transit Authority inter-modal facility.

In 2011 the BTA moved a covered hopper rail-car, built in 1974, to the bus terminal in recognition of the former Pullman-Standard plant.

In 1940, lead engineer Karl Probst led Bantam design team to create what later was termed the iconic WWII Jeep.

The Mars route closed in April 1931, followed by the Evans City line on August 15, 1931, with the trolleys replaced by buses.

Thomas Matthew Crooks, the perpetrator, was promptly killed by a Secret Service Counter Assault Team sniper.

[14] Trump was swiftly transported to Butler Memorial Hospital and treated there, before being flown out of Pittsburgh International Airport.

Nonetheless, Mayor of Butler Bob Dandoy stated that a lot of attention was focused on the city.

[16] According to the United States Census Bureau, the city has a total area of 2.7 square miles (7.0 km2), all land.

At the time, the Armco Inc. steel facility in Butler ranked first nationally for the amount of pollutant discharges.

[17] However, by 2010, due to reduced industry and clean up efforts, the creek's health has significantly recovered and has become popular for water-sport activities.

Stewart O'Nan's prizewinning 1994 novel Snow Angels is set in Butler, with the protagonist being a local high school student.

The Butler Italian Festival is an annual street fair that features ethnic foods, live music and events.

Butler County Airport, in Penn Township,[36] is used for general aviation and may accommodate large aircraft such as corporate jets.

[citation needed] Butler Farm Show Airport, in Connoquenessing Township,[37] is used by pilots with smaller, private aircraft.

Five major highways run through or near the city, providing links to other areas throughout Western Pennsylvania.

[38] That year, Mayor Bob Dandoy, a Democrat, stated that the city limits has a higher concentration of non-Republicans compared to the surrounding county.

[39] Even though the event took place outside of city limits in Butler Township, the City of Butler issued a statement expressing sympathy for the death of Corey Comperatore, a firefighter caught in the line of fire, and for the attempt on Trump's life.