One of the most infamous political rivalries in modern American history did not play out on debate stages or campaign trails. It simmered behind closed doors, whispered through clenched teeth in the corridors of power, and occasionally erupted in moments so petty and personal they bordered on the absurd. This rivalry did not center on President John F. Kennedy himself, nor on any Republican opponent. Instead, it revolved around two men locked in a mutual loathing so intense it defined an era: Attorney General Robert F. Kennedy and Vice President Lyndon Baines Johnson.

Their hatred was not subtle. It announced itself through insults disguised as jokes and nicknames sharpened into weapons. Kennedy referred to Johnson as “Uncle Rufus” or “Rufus Cornpone,” mocking his crude speech, lumbering posture, and what he viewed as a complete lack of refinement. Johnson, never one to remain silent, fired back by calling Kennedy a “grandstanding runt” and a “snot-nosed kid.” For the sake of party unity, this venom was kept mostly out of public view, but within the White House, it was an open secret. At one point, Kennedy was reportedly gifted a voodoo doll of Johnson, which he stabbed with pins for amusement—an act that, while almost cartoonish, symbolized just how deep the animosity ran.

At first glance, the hostility seemed easy to explain. Johnson had once been the Senate Majority Leader, arguably the second most powerful man in the country during the Eisenhower years. Now, as vice president, he occupied a role notorious for its irrelevance. Meanwhile, Robert Kennedy—nearly twenty years younger—served as attorney general and the president’s closest advisor, a position many believed he earned solely because of his last name. But the roots of their hatred reached far deeper, stretching back decades before either man set foot in the White House.

The origin story of this feud may trace back to 1940, when President Franklin D. Roosevelt fired Ambassador Joseph P. Kennedy, Robert’s father. Lyndon Johnson, then a young congressman, was present when Roosevelt reportedly referred to Joe Kennedy with open contempt. Johnson loved retelling the story, framing it as a rich snob getting what he deserved. For the Kennedy family, it was a humiliating blow to a patriarch they revered. Robert Kennedy was still a child, but the insult lingered, passed down and hardened over time. As Joe Kennedy once remarked, “Once Bobby hates you, you stay hated.”

Their first personal encounter in 1953 set the tone for everything that followed. Johnson, already a powerful senator, entered a cafeteria where Senator Joseph McCarthy and his staff were seated. Everyone stood to greet Johnson—everyone except Robert Kennedy. He remained seated, glaring. Johnson, ever the master of dominance, walked over and forced the issue, standing over Kennedy until he rose and shook his hand without making eye contact. Johnson later explained the tension simply: it was about Roosevelt and the father. He knew exactly why Kennedy despised him.

By 1960, their rivalry reached a boiling point. Johnson lost the Democratic presidential nomination to John F. Kennedy, a defeat he considered humiliating. To Johnson, Kennedy’s success was not the result of political skill but of inherited wealth and superficial charm. When Johnson accepted the vice-presidential slot, he did so begrudgingly, aware that he was now playing second fiddle to a man he deeply resented. Robert Kennedy, for his part, tried repeatedly to block Johnson from accepting the position, confronting him directly in private meetings that left witnesses uneasy. No one knows what was said behind those closed doors, but the outcome was clear: Johnson joined the ticket, and the hatred only intensified.

At the heart of this conflict were two fundamentally incompatible personalities. Robert Kennedy was driven by moral absolutism. He despised dishonesty, hated sycophants, and refused to compromise his sense of justice—even when it cost him politically. Lyndon Johnson was the opposite: a master of compromise, manipulation, and raw power. He flattered when it suited him, intimidated when it didn’t, and demanded unwavering loyalty from those around him. To Kennedy, Johnson embodied everything wrong with politics.

During John F. Kennedy’s presidency, Robert wielded immense influence, often sidelining the vice president. Johnson seethed, watching from the margins as the younger man whispered in the president’s ear. After the assassination, the power dynamic flipped, but the resentment remained. Kennedy refused to show Johnson the deference he demanded, openly challenging him, especially over Vietnam—a war Kennedy increasingly opposed and Johnson relentlessly escalated.

Even as Johnson pushed through landmark legislation, including civil rights reforms that fulfilled much of Kennedy’s legacy, he lived under the shadow of Robert Kennedy’s popularity and ambition. That shadow haunted him until 1968, when Robert Kennedy was assassinated. Johnson, despite his achievements, never escaped the feeling that history would remember the Kennedys more fondly.

When Johnson died in 1973, four years after leaving office, he was still grappling with that legacy. The rivalry had consumed both men, shaping their decisions and defining their public images. And yet, begrudging respect lingered beneath the hatred. Robert Kennedy once admitted that despite everything, Johnson was “the most formidable human being” he had ever met. It was a rivalry born of ego, hardened by history, and destined to leave scars on a nation.