| Name | Dam of Winthrop (US) |
| YoB | |
| Sex | mare |
| Colour | |
| Sire | Eaton Horse (US), 1840 |
| Dam | Niles Mare (US) |
| Damsire | |
| Breeder | |
| Birthplace |
| Dam of Winthrop (US) | Eaton Horse (US), 1840 | Avery Horse (US) | |
| Buller's Mare of Anson (US) | Winthrop Messenger (Maine Messenger) (US), 1807 | ||
| Niles Mare (US) | |||
| Colour | Gender | Pedigree | Breeder | ||
|---|---|---|---|---|---|
| 1864 | Winthrop (US) | bay | horse | Drew Horse (US), 1842 - Dam of Winthrop (US) | E. J. Greene |