Four days after the Lawrence Massacre, on August 25, 1863, General Ewing retaliated against the Confederate guerrillas by issuing General Order No.
11, an evacuation order that evicted almost 20,000 people from four counties in rural western Missouri and burned many of their homes.
The order was intended to undermine the guerrillas' support network in Missouri.
On October 2, a group of 450 guerrillas under Quantrill's leadership met at Blackwater River in Jackson County and left for Texas.

They departed earlier in the year than they had planned, owing to increased Union pressure.
En route, they entered Baxter Springs, Kansas, the site of Fort Blair.
They attacked the fort on October 6, but the 90 Union troops there quickly took refuge inside, suffering minimal losses.
Shortly after the initial assault, a larger group of Union troops approached Fort Blair, unaware that the fort had been attacked and that the men they saw outside the fort dressed in Union uniforms were actually disguised guerrillas.
The guerrillas charged the Union forces, killing about 100.
Anderson and his men were in the rear of the charge, but gathered a large amount of plunder from the dead soldiers, irritating some guerrillas from the front line of the charge.
Not satisfied with the number killed, Anderson and Todd wished to attack the fort again, but Quantrill considered another attack too risky.
He angered Anderson by ordering his forces to withdraw.

On October 12, Quantrill and his men met General Samuel Cooper at the Canadian River and proceeded to Mineral Springs, Texas to rest for the winter.
During the winter, Anderson married Bush Smith, a woman from Sherman, Texas.
Anderson ignored Quantrill's request to wait until after the war and a dispute erupted, which resulted in Anderson separating his men from Quantrill's band.
The tension between the two groups markedly increased—some feared that open warfare would result—but by the time of the wedding, relations had improved.
In March 1864, at the behest of General Sterling Price, Quantrill reassembled his men, sending most of them into active duty with the regular Confederate Army.
He retained 84 men and reunited with Anderson.
Quantrill appointed him a first lieutenant, subordinate only to himself and to Todd.

A short time later, one of Anderson's men was accused of stealing from one of Quantrill's men.
Quantrill expelled him and warned him not to come back, and the man was fatally shot by some of Quantrill's men when he attempted to return.
It is likely that this incident angered Anderson, who then took 20 men to visit the town of Sherman.
They told General Cooper that Quantrill was responsible for the death of a Confederate officer; the general had Quantrill arrested.
Sutherland described Anderson's betrayal of Quantrill as a "Judas" turn.
Quantrill was taken into custody but soon escaped.
Anderson was told to recapture him and gave chase, but he was unable to locate his former commander and stopped at a creek.
There, his men briefly engaged a group of guerrillas loyal to Quantrill, but no one was injured in the confrontation.
Upon returning to the Confederate leadership, Anderson was commissioned as a captain by General Price.
Four days after the Lawrence Massacre, on August 25, 1863, General Ewing retaliated against the Confederate guerrillas by issuing General Order No. 11, an evacuation order that evicted almost 20,000 people from four counties in rural western Missouri and burned many of their homes. The order was intended to undermine the guerrillas' support network in Missouri. On October 2, a group of 450 guerrillas under Quantrill's leadership met at Blackwater River in Jackson County and left for Texas.
They departed earlier in the year than they had planned, owing to increased Union pressure. En route, they entered Baxter Springs, Kansas, the site of Fort Blair. They attacked the fort on October 6, but the 90 Union troops there quickly took refuge inside, suffering minimal losses. Shortly after the initial assault, a larger group of Union troops approached Fort Blair, unaware that the fort had been attacked and that the men they saw outside the fort dressed in Union uniforms were actually disguised guerrillas. The guerrillas charged the Union forces, killing about 100. Anderson and his men were in the rear of the charge, but gathered a large amount of plunder from the dead soldiers, irritating some guerrillas from the front line of the charge. Not satisfied with the number killed, Anderson and Todd wished to attack the fort again, but Quantrill considered another attack too risky. He angered Anderson by ordering his forces to withdraw.
On October 12, Quantrill and his men met General Samuel Cooper at the Canadian River and proceeded to Mineral Springs, Texas to rest for the winter. During the winter, Anderson married Bush Smith, a woman from Sherman, Texas. Anderson ignored Quantrill's request to wait until after the war and a dispute erupted, which resulted in Anderson separating his men from Quantrill's band. The tension between the two groups markedly increased—some feared that open warfare would result—but by the time of the wedding, relations had improved. In March 1864, at the behest of General Sterling Price, Quantrill reassembled his men, sending most of them into active duty with the regular Confederate Army. He retained 84 men and reunited with Anderson. Quantrill appointed him a first lieutenant, subordinate only to himself and to Todd.
A short time later, one of Anderson's men was accused of stealing from one of Quantrill's men. Quantrill expelled him and warned him not to come back, and the man was fatally shot by some of Quantrill's men when he attempted to return. It is likely that this incident angered Anderson, who then took 20 men to visit the town of Sherman. They told General Cooper that Quantrill was responsible for the death of a Confederate officer; the general had Quantrill arrested. Sutherland described Anderson's betrayal of Quantrill as a "Judas" turn. Quantrill was taken into custody but soon escaped. Anderson was told to recapture him and gave chase, but he was unable to locate his former commander and stopped at a creek. There, his men briefly engaged a group of guerrillas loyal to Quantrill, but no one was injured in the confrontation. Upon returning to the Confederate leadership, Anderson was commissioned as a captain by General Price.
William T. Anderson