White flight from the area in the 1960s, and a strong influx of African Americans eager to take advantage of inexpensive housing, radically changed the demographic nature of the neighborhood.

Union–Miles Park is bordered on the west by Broadway–Slavic Village, the northwest by Kinsman, the north by Mount Pleasant, the east by the Lee–Miles area, and the south by the city of Garfield Heights, Ohio.

The semi-permanent encampments of the Woodland people were usually atop high bluffs overlooking major river valleys, and consisted of low earthen walls and shallow ditches, which led early white settlers to mistakenly characterize them as "forts".

By the time the Iroquois of what is now central New York began moving along the shore of Lake Erie into northeast Ohio in 1650 during the Beaver Wars, the area was almost uninhabited.

[22] The second "fort" was located near what is now the CanalWay Center of the Ohio & Erie Canal Reservation of the Cleveland Metroparks, and consisted of earthen walls approximately 6 feet (1.8 m) high, with a ditch in front of them.

Although the mouth of the Cuyahoga River initially drew the most settlers, a great many of these families moved into the highlands of Newburgh Township after finding their original homesteads prone to malaria.

[72] In 1850, the United States Census showed that Newburgh Township was the fifth-most populous incorporated area in Cuyahoga County, with 1,542 residents[77] living in 259 families in 246 dwellings.

[79] The agricultural economy of Newburgh Township was limited as most farms were small (no more than 100 acres (400,000 m2) in size) and numerous dry ravines cut across the arable land.

Although Grasselli Chemicals was located outside the Union–Miles Park neighborhood, Czech and Polish immigrants, seeking work in the plant, began settling along Broadway Avenue nearby.

[105] On November 9, 1862, Stone, Chisholm & Jones reorganized and became the Cleveland Rolling Mill after receiving investments from Henry B. Payne, Jeptha Wade, and Stillman Witt.

[111] The company built a 60-foot (18 m) high, 16-foot (4.9 m) wide blast furnace in 1864 near the west end of what is now Saxe Avenue,[112] and the following year erected its first Bessemer converter.

[145] The Union–Miles Park iron and steel mills—and the associated factories which turned these products into bolts, machinery, nails, plate, rods, tools, and other items—were largely concentrated in the central and western sections of the neighborhood.

[148] The emergence of the steel industry encouraged a large number of Irish, Welsh,[149][150] and, to a much lesser extent, Scottish[111] immigrants to move to the area to work in the mills.

[152][aa] Another Irish community formed on Gaylord Avenue southeast of the Cleveland Rolling Mill, which led people to refer to this part of Union–Miles Park as Irishtown.

[174] The congregation initially worshipped on the second floor of the Newburgh Village town hall until its church home was erected at the corner of E. 93rd Street and Miles Park Avenue later that year.

[185] In 1916, the lodge contracted with local architect William J. Carter to design and build the Newburgh Masonic Temple six blocks to the southeast at 8910 Miles Park Avenue.

[203][af] The road's line entered the Union–Miles Park neighborhood at what would later be Calvary Cemetery, ran north to the southern end of the Cleveland Rolling Mill site, then turned southwest and west to follow Morgan's Run before crossing the Cuyahoga River near the Clark Avenue Bridge.

The line, which began construction in 1899 and was complete in 1904, was intended to link the Newburgh area iron and steel plants with those on the Cuyahoga River and near the port of Cleveland.

The line began at the company's Central Furnaces and ran briefly south before turning west and crossing the Cuyahoga River at the now-demolished Jefferson Avenue Bridge.

[253] In 1905, one of the major landmarks of the area was radically changed when the Cleveland and Pittsburgh Railroad (C&P) won approval of a plan to build new, wide tracks on the south side of Broadway Avenue in order to eliminate an at-grade crossing nearby.

Founded by C. C. Bohn, E. E. Allyne, Daniel Ryan, and Rollin H. White, it manufactured automobile cylinders and hard-to-cast items at its plant at Aetna Road and E. 91st Street.

The first 10.08-mile (16.22 km) section, from Rockport to the Lake Erie and Pittsburgh Railway (a block south of the intersection of Broadway and Harvard Avenues in the Slavic Village neighborhood, an area known to railroads as "Marcy") opened on February 24, 1910.

[310] Lake Erie Chemicals would retain ownership of the structure after the war, and it housed a wide variety of small manufacturers until 1957 when Braden Sutphin Ink purchased and moved into the building.

Many absentee property owners no longer gave their homes the right amount of maintenance, and mortgage defaults, foreclosures, and sheriff's sales became common.

[62] Cleveland had long suffered from racially discriminatory practices by lending institutions,[330][331] and in 1979 residents of Union–Miles Park began picketing lenders, including the Federal Housing Administration (FHA).

[348][351] In the spring of 1979, 100 block clubs in the neighborhood formed an umbrella group, the Union-Miles Community Coalition, to work more effectively as an advocate for improved housing and city services in the area.

[356] To enable it to take on increasingly complex problems requiring full-time staff and public and private financing, the coalition formed the nonprofit Union Miles Development Corporation (UMDC) on May 1, 1981.

Area priests had been filling in on a temporary basis, but illness and other duties deprived the congregation of its last pastor in late 1992 so the diocese decided to close the church.

Cleveland Metroparks and the Slavic Village Development Corp. spent $1.2 million ($2,000,000 in 2023 dollars) building observation decks and restoring a nearby 19th-century home (which was converted into the Mill Creek Falls Historic Center).

The property crime[aq] rate was slightly lower than the city average, and tended to be concentrated in the industrial district on the western edge of the neighborhood.