Heyer's earliest works were romance novels, most set before 1800. In 1935, she released "Regency Buck", her first novel set in the Regency period. This bestselling novel essentially established the genre of Regency romance. Unlike romantic fiction of the period by other writers, Heyer's novels featured the setting as a plot device. Many of her characters exhibited modern-day sensibilities; more conventional characters in the novels would point out the heroine's eccentricities, such as wanting to marry for love. The books were set almost entirely in the world of the wealthy upper class and only occasionally mention poverty, religion, or politics.