( CNN ) -- This year will mark 51 years since President John F. Kennedy was assassinated in Dallas on November 22 , 1963 . Whether you were alive at the time or not , you probably know that Lee Harvey Oswald killed the President , only to be fatally gunned down by Jack Ruby two days later . You probably also know there are hundreds of conspiracy theories about who was behind the assassination , and whether Oswald was the lone gunman or if there was another shooter on the infamous grassy knoll . Here are five things you may not know about the assassination of the 35th president of the United States : . 1 . Oswald was n't arrested for JFK killing . Lee Harvey Oswald was actually arrested for fatally shooting a police officer , Dallas patrolman J.D . Tippitt , 45 minutes after killing Kennedy . He denied killing either one and , as he was being transferred to county jail two days later , he was shot and killed by Dallas nightclub operator Jack Ruby . 2 . Assassinating the president was n't a federal crime in 1963 . Despite the assassinations of three U.S. presidents -- Abraham Lincoln , James Garfield and William McKinley -- killing or attempting to harm a president was n't a federal offense until 1965 , two years after Kennedy 's death . 3 . TV networks suspended shows for four days . On November 22 , 1963 , at 12:40 p.m. CST -- just 10 minutes after President Kennedy was shot -- CBS broadcast the first nationwide TV news bulletin on the shooting . After that , all three television networks -- CBS , NBC , and ABC -- interrupted their regular programming to cover the assassination for four straight days . The JFK assassination was the longest uninterrupted news event on television until the coverage of the September 11 attacks in 2001 . 4 . It led to the first and only time a woman swore in a U.S. president . Hours after the assassination , Vice President Lyndon Johnson was sworn in as president aboard Air Force One , with Jacqueline Kennedy at his side , an event captured in an iconic photograph . Federal Judge Sarah Hughes administered the oath , the only woman ever to do so . 5 . Oswald had tried to assassinate Kennedy foe . Eight months before Oswald assassinated JFK , he tried to kill an outspoken anti-communist , former U.S. Army Gen. Edwin Walker . After his resignation from the U.S. Army in 1961 , Walker became an outspoken critic of the Kennedy administration and actively opposed the move to racially integrate schools in the South . The Warren Commission , charged with investigating Kennedy 's 1963 assassination , found that Oswald had tried to shoot and kill Walker while the retired general was inside his home . Walker suffered minor injuries from bullet fragments .
President John F. Kennedy was assassinated on November 22 , 1963 . The assassination of the 35th president is considered to be one of the most significant events in American history and has been a source of controversy ever since it occurred. Investigations over the decades revealed countless facts -- and new questions about the case .