On February 13

On this day in ...
... 1542, Catherine Howard was beheaded for adultery at the Tower of London. Of this queen (below right), the 5th of 6 wives of the English King Henry VIII, this website writes:

Catherine Howard did not have an impact upon English history. She is perhaps the most inconsequential of Henry VIII's six wives, her reign as queen a very brief eighteen months. She bore no children and made no lasting impression upon those who knew her. But it should be remembered that she was thirty years younger than her husband, a silly young girl who never understood the dangers of royal regard. Her life was over before it had truly begun; we can only wonder how it might have ended differently.

Not a word of fault found with the fatally fickle king.
... 1961, officials in the province of Katanga announced that the man who'd served from June to September 1960 as Congo's 1st Prime Minister, Patrice Lumumba, was dead. It was claimed that Lumumba (below left) had been "killed by villagers trying to take him into custody"; however, years later that was deemed not to be the whole truth. According to the BBC:

A Belgian Government inquiry into the murders reported in November 2001 that they would not have taken place without the complicity of Belgian and American intelligence services.
In February 2002 the Belgian Government made its first official apology for its part in the assassinations and has set up a $3m fund to encourage democracy and development in the Democratic Republic of Congo.

On September 14, ...

... 1960, Col. Joseph Mobutu seized control in Congo. He "suspended" the new president and 2 prime ministers in the country, which had won independence from Belgium just 10 weeks earlier. Prime Minister Patrice Lumumba fled; after numerous attempts, assassins ended his life in February 1961. Securing control in 1965 and adopting the name Mobutu Sese Seko, the onetime colonel ruled the country, which he renamed Zaire, until the mid-1990s.
... 1927 (80 years ago today), Isadora Duncan (left) died in Nice, France. A half-century earlier she'd been born in San Francisco, to a poet father and a "Victorian lady" of a mother, who divorced when she was a child. Eventually finding her way to Europe, Duncan became a dancer and choreographer. As is evident in the video below, she was renowned for her penchant for bare feet and neoclassical drapery. Sympathetic to Lenin's Soviet experiment, she lived and worked in Moscow in the early 1920s. Duncan died in a scene of high drama: while a passenger in a sports car, her long neckscarf caught in the wheel, strangling her.