Background
Fear of slave rebellion was widespread among white people across the antebellum South, fueled by rare but real events such as Nat Turner's rebellion. In Texas, the enslaved population had more than tripled in the decade before 1860, and white Southerners were increasingly anxious that the growing abolitionist movement would organize revolts. Local governments in Texas had already expelled Tejano residents on suspicion of being unsupportive of slavery — Uvalde, for example, passed a law in 1857 requiring Mexicans to obtain a permit even to pass through the county — and Tejanos had been killed in the Cart War and other attacks. Following John Brown's 1859 raid on Harpers Ferry, Texans also targeted abolitionist ministers, and vigilantes in Palestine, Texas burned textbooks they considered part of an abolitionist conspiracy.
The Panic
On July 8, 1860, fires broke out in more than a dozen Texas towns, damaging parts of Dallas, Denton, Pilot Point, and other communities. The fires were likely caused by extremely hot, dry weather — 110°F (43°C) was reported in Dallas that day — combined with stores of white phosphorus matches that could spontaneously combust in high heat. While many residents initially accepted the weather explanation, vigilantes in Dallas began torturing Black residents to extract confessions of arson. Three men — Patrick Jennings, Sam Smith, and Cato — were executed as scapegoats. Charles R. Pryor, editor of the Dallas Herald, wrote widely reprinted letters describing the fires as a deliberate conspiracy orchestrated by two allegedly abolitionist Methodist ministers, intended to spark a slave revolt around an upcoming election.
Panic spread across Texas, and communities formed vigilance committees that used tortured confessions to construct an elaborate, imagined conspiracy involving a white command structure directing Black arsonists, assassins, poisoners, and "wife-stealers." Reports of arson attempts and abolitionist murder plots proliferated; in Austin, the mayor's office reported finding weapons caches in slave quarters, presumed to belong to unidentified white conspirators. Night patrols targeted enslaved people, white Northerners, foreigners, and Mexican Texans, killing those who failed to satisfy questioning, while others were subjected to show trials and public hangings. Law enforcement largely allowed vigilantes to carry out these killings. Fort Worth's vigilance committee stated it was "better ... to hang ninety-nine innocent men than to let one guilty one pass." Historians estimate 30 to 100 people were killed, with no hard evidence ever produced proving guilt in any case.
Effects
Pro-slavery advocates used the alleged conspiracy to build support for secession, attributing it to supporters of Abraham Lincoln and blaming the Wide Awakes organization for the fires. This rhetoric helped convince previously pro-Union Texans that secession was necessary if Lincoln won the presidency, which occurred in November 1860; Texas seceded in 1861. The conspiracy was treated as historical fact by some journalists and scholars into the mid-20th century despite lacking evidentiary support. Some participants in the 1860 killings, including future Texas Governor Richard Coke, went on to prominence, while the events themselves faded from public memory. In 1991, a park near Dealey Plaza in Dallas was renamed Martyrs Park to commemorate the execution site of Patrick Jennings, Sam Smith, and Cato.