Dunkirk was considered to be founded by Fredonian Walter Smith, and was settled after Fredonia due to thick forest which covered the lake plain and made it more difficult to clear for settling. Although one of the last communities in the county to incorporate as a village, Dunkirk was the first city, beating Jamestown by six years.
Horatio G. Brooks, founder of Brooks Locomotive Works, was the first elected mayor. The city reached its peak population of nearly 20,000 people during the 1920s.
One of the first brick buildings built in the city was a jail, located on Third Street east of what is now Central Avenue. Although a library had been in operation previously, in 1903 philanthropist Andrew Carnegie donated money for the building of what is now the Dunkirk Free Library.
During World War II, up to 425 Italian and German prisoners of war were held at the Chautauqua County fairgrounds on Central Avenue.
The Dunkirk Harbor was once home to several fishing companies with some 15 to 20 tugs leaving the harbor daily during the 1880s. Overfishing, pollution, unregulated Canadian competition and finally, New York state regulations, all played a role in the demise of the local fishing industry. The city pier was built in 1913 and renovated, beginning in 1977.
Construction on the original Dunkirk Lighthouse began in 1826 with the lighthouse in operation in 1827, until it was razed in 1875 and replaced with the present structure, west of the original.
The first school in Dunkirk was built in 1827 at the southeast corner of Central Avenue and Third Street. School No. 1 was constructed in 1857 on the southwest corner of what is now Washington Avenue and East Fourth Street. The Dunkirk Union Free School District began in 1858 as a result of an act of the state Legislature.
On July 13, 1898, a hospital association was formed to run what would become Brooks Memorial Hospital.