After the war Johnson lived for a while in Mexico City, boxing, wrestling, bullfighting and enjoying high times with a group of hard-drinking generals and cientificos, or mining millionaires. He was also on good terms with President Venustiano Carranza. But General Alvaro Obreg�n was now the coming man; Carranza began to feel the heat and laid plans for a fast getaway. The statesman was kind enough to pass the word to Johnson, who felt that he, too, might be unpopular with the new ruler and got out of town well ahead of Obreg�n's advance.
Johnson's destination was Tijuana, just below the U.S. line in Lower California. Here he planned to open a caf� and promote and engage in prizefighting.
Less than a year later, after only modest success in promoting fights, Johnson began to pine for the U.S., and in particular for Chicago. And with his usual incorrigible optimism he made himself believe that somebody or other would have the influence to work out a settlement of his law trouble. This belief was partly based on an interview with Tom Carey, a Chicago politician who visited Tijuana and advised Johnson to come home. But Carey made no promises. He merely gave the opinion that whatever happened it would be better for Johnson to return while still a comparatively young man than to spend the rest of his life in exile.
Johnson's surrender to federal authorities in San Diego on July 20, 1920 brought out headline type of a size that the newspapers had not used since Armistice Day. This may have been why Johnson continued to believe he would receive official forgiveness right up to the time he was brought to court on Sept. 13 and again faced Judge George Carpenter. He could scarcely have been more wrong. The judge saw no reason to mitigate his original views and ordered Johnson to "The Walls"—the Federal Penitentiary at Leavenworth, Kans.—to serve out his time of a year and a day.
However, Johnson's stay at The Walls was not onerous. Upon admission he was brought before the superintendent, who proved to be none other than ex-Governor Denver S. Dickerson of Nevada, an old friend from the time of the Jeffries fight at Reno in 1910. Dickerson talked to Johnson in a fatherly way.
"You play square with me, Jack," said the official, "and you won't find things too bad here. Now, what job do you want while you're with us?"
Johnson put in for prison physical director, and it was so ordered. His duties were to organize and direct calisthenic drills, and as entertainment for the prisoners he fought five heavyweights brought in from outside. Johnson made himself very comfortable in prison and managed to keep a good supply of liquor and cigars and employed his own cook from among the inmates.
Johnson was released, with time off for good behavior, on July 9, 1921 and as a last favor to Superintendent Dickerson delivered an inspirational address to the prison population before checking out. In this memorable performance Johnson showed that he was beginning to feel his way into a vocation as an exhorter toward the better things of life. He took no particular subject for his address to the prisoners, recalling later that he wandered in a rather wide field, "having for my topics religion, squareness, courage and successful living." The prisoners gave three cheers, Dickerson escorted Johnson to the gates, and he walked out a free man amid the braying of a brass band which had marched to meet him. Except for exceeding speed limits he never again took liberties with the law.
Chicago, his old home, gave Johnson a roaring welcome without any of the racial friction feared by the police, and New York, his next stop, proved almost as enthusiastic. Jack then took to the road in vaudeville, attracting much less condemnation—and smaller audiences—than would have been the case a short time before. But the years which now came on, though never very prosperous, were by no means quiet and secluded. As it turned out, Johnson was to enliven many of his public appearances by a gift for extemporaneous chatter in a mystical, allusive style somewhat akin to that of his great contemporaries James Joyce and Father Divine. By the late '20s Johnson's lectures had taken a moralizing turn, and he mounted the pulpit more than once to exhort church audiences. He said that his theory of homiletics was to have no set text but to weave a general discourse around "Job, Saul, Esau, Esther and Revelations." On one occasion he preached to a gathering of Methodist bishops, urging them to keep control of themselves at all times and above all to avoid liquor, which could get a hold of a man before he knew it and quickly drag him to disaster. Another notable public address was delivered in 1924 when Johnson appeared before a klavern of the Ku Klux Klan in Danville, Ill., speaking mainly on sportsmanship, fair play and the golden rule.
The following year, Johnson's marriage to Lucille Cameron ended in divorce. He soon married Mrs. Irene Pineau, herself recently divorced, and lived with this fourth (and third white) wife for the rest of his days. Though his earning power was painfully reduced, he kept busy hunting for sideshow engagements and lecture dates, usually paid his bills and always had a fast car to drive, appearing in traffic courts with ominous regularity. He went off the road in Connecticut and followed that by miraculously escaping unhurt from a smashup outside Benton Harbor, Mich. in 1925. "I must confess to having a weakness for fast driving," Johnson said, and later announced that he would race professionally. Fortunately, he received so little encouragement that he gave up this idea.