Gunness immigrated to the United States in 1881 and married Mads Sorenson in 1884. They had four children together, but all of them died in infancy. In 1894, Sorenson died under suspicious circumstances, and Gunness collected $8,500 in life insurance money.
After Sorenson's death, Gunness moved to Chicago and began working as a dressmaker. She soon met and married Peter Gunness, a carpenter. The couple had a daughter together, but the baby died in 1900.
In 1902, Peter Gunness was found dead in his barn, with his skull crushed. Gunness collected $8,000 in life insurance money.
After Peter's death, Gunness began advertising for husbands in the newspapers. She married several men, but they all mysteriously died under suspicious circumstances. In 1908, Gunness's house burned down, and she and her children were found dead inside.
The authorities found suspicious injuries on Gunness's body, indicating that she had probably killed her children. They discovered that she had purchased arsenic and embalming fluid, which led them to believe that she had used these chemicals to murder her victims.
Gunness's case remains one of the most infamous unsolved mysteries in American history. Her crimes were particularly shocking because she killed her victims indiscriminately, without any apparent motive.