George Warleggan is the primary antagonist of Winston Graham's Poldark novels and its TV adaptions. He was portrayed by Ralph Bates in the 1975 series and by Jack Farthing in the 2015 series.
George is a greedy and ruthless banker seeking to buy out the copper mines in Cornwall and turn the industry into a monopoly controlled by the Warleggans, at the expense of anyone who stands in his way, including the Poldarks. He manipulates Francis Poldark (cousin of Ross Poldark, George's archrival) by befriending him only to bankrupt him through a gamble at the hands of his cousin Matthew. George later regains Francis' trust by returning what he lost in exchange for the name of the shareholders investing in Ross's smelting company. Because many of Ross's shareholders bank with the Warleggans, George calls in their debts, essentially bankrupting them and putting a stop to Ross's mine operations.
He also attempts to woo Elizabeth, Francis's wife and Ross's first love.