There was a time when famed hedonistic hostess Rebekah Harkness despised parties. “These stuffy society functions represented everything she hated,” writes Craig Unger in Blue Blood—the definitive biography of Harkness, an American heiress, socialite and arts patron best known to this generation for inspiring Taylor Swift’s 2020 song “The Last Great American Dynasty.” In 1933, Swift’s muse was an 18-year-old debutante and already one the most famous (and most rebellious) women in St. Louis, Missouri. According to Unger’s book, with her inner circle by her side—a self-proclaimed “Bitch Pack” of finishing school rebels prone to partying until dawn—Harkness once arrived at a party by climbing onto the roof and sliding down the chimney, she hijacked cars for joyrides, swore and skinny-dipped, and, to the absolute horror of her conservative stockbroker father, performed a semi-striptease on a dining room table. She set a high bar for partying, and a century later—in Harkness’s own decadent Rhode Island mansion, which Swift bought in 2013 with nearly $18 million in cash—the singer and her “Friend Squad” have kept the …