One of the most colorful characters to come to White Plains was William Muldoon.

Standing five feet ten, 180 pounds, Muldoon became America's wrestling champion in 1879. He invented the medicine ball, believed in proper diet and exercise, and hot water drinks.

In 1886, Muldoon wrestled with and beat the famous John L. Sullivan, the champion prize fighter. Three years later he trained Sullivan for his fight with Jake Kilrain. In spite of Sullivan's high living, with Muldoon as his ringside second, Sullivan won in Round 75.

Muldoon also trained Sullivan for the James Corbett fight, but his fighter failed to heed his instructions. Sulllivan was felled by Corbett, who was thirty pounds lighter, and Muldoon refused to train Sullivan again.

About 1890, Muldoon purchased the Carhart mansion and established his Hygienic Institute in the building. He rehabilitated men who had "made fools of themselves for so long they had forgotten the art of living," and those who were overworked mentally, needed a rest, or wanted to reduce.

In 1894, the famous woman journalist, Nellie Bly, having taken the White Plains Keeley Institute cure, angled herself into Muldoon's Institute. Nellie, reporting her experiences there, mentioned that the mansion, with its opulent interiors, had cost $100,000 to construct.

In May 1897, Robert Fitzsimmons was a guest, and three weeks later, ex-champ Sullivan arrived for a special course. He lasted less than two weeks. When Muldoon caught him drinking, Sullivan was expelled from the institution.

When Muldoon first came to White Plains, the townspeople were not happy. They considered him a "sport" who worked with fighters and surrounded himself with "gangs of toughs." It was not long, however, before they were welcoming the celebrity living amongst them, and looked forward to the frequent times he was seen striding the streets of the village, clad in a white overcoat, and trailed by a Saint Bernard dog, "as big as a Shetland pony."

He continued an interest in the village even after he relocated to Purchase about 1900. On November 22, 1908, he participated in the celebration of the 225th anniversary of the purchase of White Plains, and personally led the first division in the parade.

In 1924, Muldoon was appointed Chairman of the New York State Athletic Commission during the governorship of Alfred E. Smith.