Spion Kop's sire Spearmint had been Eustace Loder's most successful horse winning the Derby and the Grand Prix de Paris in 1906. At stud, he was fairly successful, siring Royal Lancer (St Leger), Zionist (Irish Derby) and Plucky Liege. Hammerkop, Spion Kop's dam was a top-class staying racehorse who won the Yorkshire Oaks in 1903 and the Cesarewitch Handicap in 1905, but produced no other winners in a long stud career.
