St. John Richardson Liddell (September 6, 1815 – February 14, 1870) was a prominent Louisiana planter who served as a general in the Confederate States Army during the American Civil War.

He was a schoolmate of future Confederate President Jefferson Davis, whom he would interact with several times during the early years of the Civil War on behalf of fellow general Albert Sidney Johnston.

Liddell commanded a division at Chickamauga in 1863, but repeatedly refused promotion to major general in order to secure an assignment closer to his plantation, which was in jeopardy from Jayhawkers.

His brigade was pivotal at Perryville and Stones' River (where his sixteen-year-old son Willie Liddell was mortally wounded), and suffered the highest percentage of casualties at Chickamauga.

Smith made several petitions for Liddell's promotion to positions including James Mouton's Texas Division, and Hardee's Chief of Staff, but these were not acted on before the war drew to a close.

In December 1864, he wrote a letter to Edward Sparrow, a Confederate Senator from Louisiana and chairman of the military Committee, expressing his conviction that the war was going against the Confederacy.

Senator Sparrow showed the letter to General Robert E. Lee, who agreed with Liddell on all points, stating that "he could make soldiers out of any human being that had arms and legs."

It was plainly clear to them after the fall of Forts Henry and Donelson that their cause was doomed unless they could concentrate their forces and wage an offensive campaign; however, political intrigue always seemed to squander any gains made by the army.

Liddell comes off as a fair, impartial officer, even proposing that had the south recruited generals like George H. Thomas, whom he considered the best Union Commander, things may have turned out differently.