burly and famous actor assaulted his victim, Nathaniel Parker Willis, in New York's Washington Square on the evening of June 17, 1850. Willis, a famous poet, essayist, and editor, was recovering from illness at the time and, in fact, had nothing to do with the seduction of Forrest's wife.
Willis, a tall man who towered over the 6-foot tall Forrest, was helpless as the whipping brought him to his knees. He was a partial-invalid, forced to near-permanent convalescence, since the late 1840s. His health aside, Willis was also noted for being somewhat effeminate, a "namby-pamby" who presented himself as a refined gentleman. At least one observer noted the "battle" may have been a man versus a woman.
Forrest was suspicious of his wife, Catherine Sinclair, as early as the spring of 1848, when he believed he found evidence of an affair. She swore her innocence, but the two separated by April 1849. Catherine moved in with the journalist Parke Godwin and Forrest filed for divorce in Philadelphia in 1850, still citing adultery. The court denied the request and Forrest was ridiculed in the press. Willis, always a sucker for gossip, joined in.
Coming to Catherine's defense, Willis wrote that Forrest violated "the American standard of what is gentlemanlike, and the American estimate of the treatment due a lady." Forrest applied for divorce again, this time in New York. It wasn't long after that Forrest whipped Willis very publicly in Washington Square.
All this tension was just the crescendo to the six-week divorce trial during the winter of 1851-1852. The city was gripped by the scandal, with "thousands and thousands" awaiting the verdict. During the trial, a witness suggested Willis and Catherine were "lying on each other" in an affair. The court finalized the divorce and, soon after, Willis sued Forrest for assault, winning $2,500 from the actor.
*Much of the information in this post comes from Sentiment and Celebrity: Nathaniel Parker Willis and the Trials of Literary Fame by Thomas Baker.