The circus had been experiencing shortages of personnel and equipment as a result of the United States' involvement in World War II.

Delays and malfunctions in the ordinarily smooth order of the circus had become commonplace; on August 4, 1942, a fire had broken out in the menagerie, killing a number of animals.

When the circus arrived in Hartford, Connecticut, on July 5, 1944, the trains were so late that one of the two shows scheduled for that day had been canceled.

[10] The tent's canvas had been coated with 1,800 pounds (820 kg) of paraffin wax dissolved in 6,000 US gallons (23,000 L) of gasoline, a common waterproofing method of the time;[4] like all hydrocarbons, both substances are hydrophobic but also highly flammable.

The big top had been erected over freshly mowed grass and exposed dirt that had been watered down and then covered with hay and wood shavings.

Inside the tent there were three rings and two stages with a 25-foot wide oval shaped track separating the performance area and seating, which could be either bleacher or un-secured folding chairs.

[12] Ringmaster Fred Bradna urged the audience not to panic and to leave in an orderly fashion, but the fire had shorted out the power and he could not be heard.

The number of actual injuries is believed to be higher than those figures, since many people were seen that day heading home in shock without seeking treatment in the city.

It is commonly believed that the number of fatalities is higher than the estimates given, due to poorly kept residency records in rural towns, and the fact that some smaller remains were never identified or claimed.

Additionally, free tickets had been handed out that day to many people in and around the city, some of whom appeared to eyewitnesses and circus employees to be drifters who would never have been reported missing.

[21] Notable survivors included; Eunice Groark (first female lieutenant governor of Connecticut), The Flying Wallendas, Charles Nelson Reilly (actor, comedian, and director), actress Jan Miner, (best known for portraying "Madge the Manicurist" in advertising for Palmolive dishwashing detergent), drummer Hal Blaine and Emmett Kelly (renowned circus clown).

Seventy years after the fire, Carol Tillman Parrish, who was six at the time, said that "until this day, I can smell the stench of human flesh" as the blaze consumed its victims.

[26] In 1991, arson investigator Rick Davey (along with co-writer Don Massey) published A Matter of Degree: The Hartford Circus Fire and Mystery of Little Miss 1565, in which he claims the girl was Eleanor Emily Cook and from Massachusetts.

Before writing the book, Davey spent six years researching the case and conducting his own experiments as to how the fire really may have started.

[28] Various assertions put forth in A Matter of Degree have been fiercely disputed by investigators who worked on the case, as well as by other writers, most notably Stewart O'Nan, who published The Circus Fire: A True Story of an American Tragedy in 2001.

Perhaps most significantly, when shown a photograph of Little Miss 1565, Eleanor's mother Mildred Corintha Parsons Cook immediately stated that it was not that of her daughter.

Badly injured in the fire, Mrs. Cook had been unable to claim her two dead children and was too emotionally traumatized to pursue it later.

Even when Little Miss 1565's picture ran in the papers, the family failed to recognize her as their own because they wished to put the traumatic event behind them.

While DNA analysis could end this debate definitively, the logistics of exhuming all of the likely candidates for this potential mix-up make such an undertaking unlikely.

In 1950, while being investigated on other arson charges, Robert Dale Segee (1929–1997), who was an adolescent at the time of the fire, confessed to starting the blaze.

Although the four were given prison terms, they were allowed to continue with the circus to its next stop, Sarasota, Florida, to help the company set itself up again after the disaster.

In 1950, Robert Dale Segee of Circleville, Ohio, claimed during a police interview that he was responsible for setting the fire.

[31] Segee, a 16-year-old roustabout for the show from June 30 to July 14, 1944, claimed that he had a nightmare in which an American Indian riding on a "flaming horse" told him to set fires.

[31] According to police authorities, Segee further stated that after this nightmare his mind went blank, and by the time it cleared the circus fire had been set.

[32] In November 1950, Segee was convicted in Ohio of unrelated arson charges and sentenced to 44 years of prison time.

However, Hartford investigators raised doubts over his confession, as he had a history of mental illness and it could not be proven that he was in Connecticut when the fire occurred.