A woman named Mansfield

It was all because of a woman named Josie.

Josie Mansfield was an American woman who became famous when one of her two wealthy lovers murdered the other. 

Jim Fisk, who operated the Erie Railroad, was the "silent partner" with Ned Stokes in his oil refinery.

In January 1871, Fisk arranged to have Stokes arrested for embezzling funds from the refinery.

They both were seeing Josie.

And Josie Mansfield likely tried to extort money from Fisk with the threat of ending their relationship and deserting him for Stokes.

On January 6, 1872, Stokes learned that Fisk was on his way to the Grand Central Hotel. He knew that Fisk always entered by the ladies entrance, so Stokes went in first and waited on the second floor landing. When he heard Fisk climbing the stairs, Stokes started down. Stokes fired two shots at Fisk from a Colt pistol, hitting him once in the abdomen and once in the left arm. Stokes tried to flee but was captured.

The first trial where he was charged with first degree murder ended in a hung jury, and rumors of jury members bribed. The second trial found him guilty of first degree murder and he was sentenced to death, a verdict overturned by appeal. The third trial concluded with a conviction for manslaughter, and Stokes served four years of a six-year prison sentence 

The next year in 1873, Josie Mansfield left New York for Paris with Ella Wesner, a male impersonator in Vaudeville

https://en.wikipedia.org/wiki/Josie_Mansfield

For a good read, 

https://www.amazon.com/Murder-Fisk-Love-Josie-Mansfield/dp/030774325X