Adolph VIII, Count of Holstein
| Adolphus XI | |
|---|---|
| Count of Holstein-Rendsburg | |
| Reign | 1427–1459 |
| Predecessor | Henry IV |
| Successor | Gerhard VII |
| Duke of Schleswig | |
| Reign | 1440–1459 |
| Predecessor | Henry IV |
| Successor | Christian I |
| Spouse |
Margaret of Höllenstein
(m. 1435) |
| House | House of Schauenburg |
| Father | Gerhard VI, Count of Holstein-Rendsburg |
| Mother | Catherine Elisabeth of Brunswick-Lüneburg |
Adolphus XI of Schauenburg (Low German: Alef or Alv, German: Adolf von Schauenburg, Danish: Adolf 8. af Holsten-Rendsborg) (1401 – 4 December 1459), as Adolph I Duke of Schleswig (Danish: Sønderjylland, formerly Slesvig), and as Adolph VIII Count of Holstein-Rendsburg, was the mightiest vassal of the Danish realm.