Dietrich introduced him to a physical romance quite different from the chaste relationship he had with Josephine, his first wife. Josie didn't get out a great deal, 
and she entertained friends and church associates at home, giving the kind of informal and formal dinner parties she had grown accustomed to as the daughter of a Central American diplomat. So when Duke would come home to relax, he was often called upon to play host to Josie's society friends and church dignitaries and he generally found such gatherings boring. Perhaps's because he was bored, or perhaps for spite, or perhaps because he simply wanted to, he began drinking to excess on such occasions. Josie thought that drinking to excess uncivilized, and she thought Duke disgusting when he was drunk. In time, whenever she planned her clergy dinners, Duke began going off to drink with his cronies. And in time he developed the habit of not coming home afterward, and this was perhaps worse for Josie, sometimes he'd come home drunk and leading a party of his friends. Josie thought no more of Duke's friends than he of hers. Duke felt that the overbearing Catholic influence on Josie was the primary cause for their incompatibility. He had wanted and had expected complete devotion from her, but in time he came to the opinion that her devotion and respect for the church were stronger and more important to her than her love for him. When he found himself in what he believed to be a loveless marriage by the tenets of the very church that he felt had rivaled him for his wife's love, he became defiant and spiteful. He began drinking heavily and seeing other women�and with a clear conscience because he believed Josie had betrayed him.
The rumors of his affairs started in 1938, when he was linked romantically with Claire Trevor. No evidence supports a romance between them, but he did have a romantic fling with Norwegian actress Sigrid Gurie, who played opposite him in Three Faces West. Miss Gurie was a sultry and aggressive woman, and Duke found her advances irresistible. Their affair ended only after Duke's agent introduced him to another of his Scandinavian clients, Danish actress Osa Massen. She never appeared in a film with Duke but she helped him with the Scandinavian accent he used in The Long Voyage Home.
These romantic interests were child's play, though, compared with his encounter with the beguiling Marlene Dietrich, with whom he starred in
Seven Sinners (1940),
The Spoilers (1942), and
Pittsburgh (1942). Dietrich, like Sigrid Gurie, was an exotically charming and extraordinarily aggressive woman who swept Duke off his feet. He was mesmerized by her. She had once had a stormy and much publicized romance with Gary Cooper, and she may have found in Duke the same qualities that had attracted her to Coop. 
Duke's relationship with her lasted longer than any of the others, and what he found particularly fascinating about her, other than her obvious interest in him, was that she shared many of his interests, including hunting , sailing, and fishing. Dietrich became Duke's best friend and confidante. She was also a hausfrau who brought home-cooked meals to the set when they were doing a movie together. They played chess during lulls in the shooting,attended football games and prizefights, and took long drives up north to Santa Barbara and San Luis Obispo on weekends. More important, she and Duke shared a passion for making movies. It is much rarer to find a shared understanding with a woman in pictures than to find a capable sex partner. Like Duke, she liked simple hearty foods�steaks and broiled fish. She drank in moderation but she was a drinker, she was a man's woman. Like Duke she had an awareness of the parts of the whole, which is unusual in an actor. "My work is my interest in life," she once said,"I have no hobbies. I have not time for anything but my work." And this was not far from the place in which Wayne had arrived. While the readers of Louella Parsons and Sidney Skolsky fancied, as they read the items, that John Wayne and Marlene Dietrich were locked in feverish embraces, they were probably running current movies at her Beverly Hills home and critically analyzing them. This too is a form of mutual affection, perhaps more enduring and more satisfying than sex.
They were inseparable for several months, and the only reason they finally went their separate ways was that Miss Dietrich had other interests and was as obsessive about her career as Duke was about his. Dietrich had a strong influence on Duke that extended from the bedroom to the boardroom. He'd been making a lot of money and spending it all. Dietirch introduced him to her business manager, a Swede name Bo Roos. The two men hit it off and Wayne hired him. Then, as quickly as it had begun, the affair ended. Duke and Dietrich didn't see each other for many years.
During the three years of his friendship with Marlene they became socially intimate, to such an extent that, for the first time, Mrs. Morrison (as Josie still called herself) became alarmed, not because she was in danger of losing her husband, for he had been lost long before, but at the scandal that might erupt. Up to now, his previous cultural exchanges with friendly European actresses had been kept discreetly private. But now she heard from her friends, and read in the columns, items about her husband and Miss Dietrich. Now this might not have signified anything carnal, because Miss Dietrich was a good friend, without being a lover, of many married men, such as Ernest Hemingway. In fact, some persons whispered that it was not in Miss Dietrich's personality to experience romance with a male. Others, on the contrary, described her as another Catherine the Great, who devoured men with an insatiable appetite.
Judged by any standards, Miss Dietrich and Wayne did not flaunt their relationship. They went out a lot in public, but then it was natural for a star to wine and dine with his leading lady. And there were often others about, friends and agents and their lady friends.
The three films they made together are gems of their kind. Lusty, fast, amusing, filled with action and fights and love. The stories were primitive. The characters were raw and virile. The scenes were violent and direct. 
Here we can see Duke developing methods of being himself, being Big John in every role, and still inventing unique qualities and mannerisms for each character, so he isn't the same and yet retains a continuity as do all the superstars from one movie to the next. Her Bijou in Seven Sinners, her Cherry Malotte in The Spoilers, and above all her Josie in Pittsburgh were all manifestations of Marlene herself. The everyday Marlene Dietrich resembled in many ways the three women she played in these films with Duke. And it was a kind of woman from whom Duke was learning to experience stimulation, intellectual and emotional. She was by far the most interesting and sensual of all the European ladies of this period in his life. She was not only his counterpoint, she was also his counterpart. The two of them were alike in so many ways that their relationship became that of two old friends. In Duke she found an actor who was an animal, an animal of honor and dignity, the sort that she always played most excitingly against, rather than the weak and helpless fools with whom she had toyed in Sternberg's pictures�which is not to detract from the splendors of Die Blaue Engel.
The off-screen friendship that developed between Duke and Dietrich probably contributed to the breakup of his first marriage, and was most certainly involved in his second. Wife number two, Esperanza Bauer, mentioned the blond star in an acrimonious divorce action, in 1953, confirming both Wayne's attachment to old friends and Dietrich's staying power.
