After the war, Forrest settled in Memphis, Tennessee, building a house on a bank of the Mississippi River. With slavery abolished, the former slave trader suffered a major financial setback. He later found employment at the Selma-based Marion & Memphis Railroad and eventually became the company president. He was not as successful in railroad promoting as in war, and under his direction the company went bankrupt.
Forrest became associated with the Ku Klux Klan movement, but he officially denied participation. Upon learning of the Klan and its goal to reinstate the "true" Southern leaders, Forrest may have remarked, "That's a good thing; that's a damn good thing. We can use that to keep the niggers in their place." (Historians disagree as to whether this quote is real.) Delegates at an 1867 KKK convention in Nashville named him the organization's honorary Grand Wizard, or leader-in-chief.
In an 1868 interview by a Cincinnati newspaper, Forrest claimed that the Klan had 550,000 members in the Southern states. He said he sympathized with them and could muster thousands of men himself.
In the interview Forrest described the Klan as "a protective political military organization...The members are sworn to recognize the government of the United States...Its objects originally were protection against Loyal Leagues and the Grand Army of the Republic..." Historians, however, have classified the Klan as a kind of guerrilla group, insurgents who refused to accept the power changes of defeat, and carried on the Civil War by other means.
Wikisource has the Text of an 1868 interview with Nathan Bedford Forrest.
In the Congressional investigation on Klan activities in 1871,[25] the committee concluded that Forrest's involvement with the Klan was limited to trying to get it to disband. They determined there was no evidence that he had founded or led the Klan.
Nearly ruined as the result of the failure of the Marion & Memphis Railroad in the early 1870s, Forrest spent his final days running a prison work farm on President's Island in the Mississippi River. There were financial failures across the country in the Panic of 1873. Forrest's health was in steady decline. He and his wife lived in a log cabin they had salvaged from his plantation.
On July 5, 1875, Forrest became the first white man to speak to the Independent Order of Pole-Bearers Association, a civil rights group whose members were freedmen. In his short speech, he stated blacks had the right to vote for any candidates they wanted and that the role of blacks should be elevated. He ended the speech by kissing the cheek of one of the daughters of one of the Pole-Bearer Memphis Appeal members, evinces Forrest's racial open-mindedness that seemed to have been growing in him. As reported in the contemporary pages of the Memphis Appeal.
"Ladies and Gentlemen I accept the flowers as a memento of reconciliation between the white and colored races of the southern states. I accept it more particularly as it comes from a colored lady, for if there is any one on God's earth who loves the ladies I believe it is myself. ( Immense applause and laughter.) I came here with the jeers of some white people, who think that I am doing wrong. I believe I can exert some influence, and do much to assist the people in strengthening fraternal relations, and shall do all in my power to elevate every man to depress none. (Applause.) I want to elevate you to take positions in law offices, in stores, on farms, and wherever you are capable of going. I have not said anything about politics today. I don't propose to say anything about politics. You have a right to elect whom you please; vote for the man you think best, and I think, when that is done, you and I are freemen. Do as you consider right and honest in electing men for office. I did not come here to make you a long speech, although invited to do so by you. I am not much of a speaker, and my business prevented me from preparing myself. I came to meet you as friends, and welcome you to the white people. I want you to come nearer to us. When I can serve you I will do so. We have but one flag, one country; let us stand together. We may differ in color, but not in sentiment. Many things have been said about me which are wrong, and which white and black persons here, who stood by me through the war, can contradict. Go to work, be industrious, live honestly and act truly, and when you are oppressed I'll come to your relief. I thank you, ladies and gentlemen, for this opportunity you have afforded me to be with you, and to assure you that I am with you in heart and in hand. (Prolonged applause.)"
Whereupon N. B. Forrest again thanked Miss Lewis for the bouquet and then gave her a kiss on the cheek[citation needed]. Such a kiss was unheard of in the society of those days, in 1875, but it showed a token of respect and friendship between the general and the black community and did much to promote harmony among the citizens of Memphis.
Forrest died in Memphis in October 1877, reportedly from acute complications of diabetes. He was buried at Elmwood Cemetery. In 1904 his remains were disinterred and moved to Forrest Park, a Memphis city park named in his honor.

Many memorials were erected to Forrest in Tennessee. Obelisks in his memory were placed at his birthplace in Chapel Hill and at Nathan Bedford Forrest State Park near Camden. A statue of General Forrest was erected in Memphis's Nathan Bedford Forrest Park. A bust sculpted by Jane Baxendale is on display at the state capitol building in Nashville. The World War II Army base Camp Forrest in Tullahoma, Tennessee was named after him. It is now the site of the Arnold Engineering Development Center.
A massive but strange statue of Forrest on horseback stands south of Nashville. Here his face takes on a comical growl, and his over sized silver body sits atop an undersized bronze mount. Both detractors and admirers of Forrest dislike this rendering so intensely that in 2002 it was reported that someone shot at it.
Tennessee has dedicated 32 historical markers linked to Nathan Bedford Forrest, more than are dedicated to the three Presidents who came from the state—Andrew Jackson, James K. Polk, and Andrew Johnson. Finally, the Tennessee legislature established July 13 as "Nathan Bedford Forrest Day."
A monument to Forrest in the Old Live Oak Cemetery in Selma, Alabama, reads "Defender of Selma, Wizard of the Saddle, Untutored Genius, The first with the most. This monument stands as testament of our perpetual devotion and respect for Lieutenant General Nathan Bedford Forrest. CSA 1821-1877, one of the south's finest heroes. In honor of Gen. Forrest's unwavering defense of Selma, the great state of Alabama, and the Confederacy, this memorial is dedicated. DEO VINDICE." As armory for the Confederacy, Selma provided most of the South's ammunition.
High schools are named for Forrest in Chapel Hill, Tennessee, and Jacksonville, Florida. Leaders in other localities have tried to remove or eliminate Forrest monuments, with mixed success.