 Heyer learned to read medieval English and created indexed files that catalogued every single day for the forty year time period.She and her husband travelled England and Scotland, where Heyer took copious notes while visiting seventy-five castles and twenty-three abbeys.After each break taken to write another Regency novel however, Heyer found it difficult to return to writing the trilogy and "recapture the spirit of her main work," as each time she had to refresh her knowledge of the era.