Quick take: Historical romance is set in a past era, with the love story shaped by that era's rules: marriage law, class, inheritance, reputation. Readers come for the escape and the constraints. The stricter the rules, the more every touch matters.
Regency (c. 1811–1820, broadly 1795–1837): British high society, the marriage mart, balls, rakes, and reputations.
Victorian (1837–1901): stricter morality, industrial change, governesses, aristocrats, and new money.
American West / frontier: ranches, homesteads, mail-order brides, lawmen and outlaws.
Wartime (WWI, WWII): soldiers, nurses, the home front, separation and reunion.
Other lanes: Scottish/Highlander, medieval, Gilded Age, Viking. Each has a loyal readership.
Regency: reformed rake, wallflower, marriage of convenience, compromised reputation, fake engagement, enemies to lovers.
Victorian: forbidden love, class difference, governess and employer, secret identity, second chance.
Western: mail-order bride, marriage of convenience, cowboy / rancher, widow or widower starting over.
Wartime: separated lovers, second chance, letters romance, love across opposing sides.
Period detail that feels authentic without stopping for a history lesson.
Language and manners that fit the era. Obvious modern phrasing breaks immersion fast.
Social stakes with teeth: ruin, disinheritance, or scandal are real consequences.
An HEA, usually a marriage.
Regency + marriage of convenience + slow burn: a bluestocking weds a duke to save her family's estate.
Victorian + class difference + forbidden love: a governess and the widowed earl she was hired to avoid.
Western + mail-order bride + second chance: the bride who arrives is the woman who jilted him years ago.
"Regency enemies to lovers romance" · "Regency marriage of convenience" · "Victorian governess romance" · "Western mail-order bride romance" · "Highlander historical romance" · "clean Regency romance"
Lead with era + trope in keywords and the first line of your blurb.
Cover cues (gowns, ballrooms, landscapes) must match the era. Readers will spot the wrong century.
State heat level clearly: historical readership splits between sweet/clean and steamy.