Ernest Günther I, Duke of Schleswig-Holstein-Sonderburg-Augustenburg
| Ernest Günther | |
|---|---|
| Duke of Schleswig-Holstein-Sonderburg-Augustenburg | |
| Reign | 13 May 1627 - 18 January 1689 |
| Successor | Frederick |
| Born | 14 October 1609 Haus Beck, Westphalia, Holy Roman Empire |
| Died | 18 January 1689 (aged 79) Augustenborg Palace, Augustenborg, Duchy of Schleswig |
| Spouse | Augusta of Schleswig-Holstein-Sonderburg-Glücksburg |
| Issue | Frederick Princess Sophie Amalie Prince Philipp Ernst Princess Sophie Auguste Louise Charlotte, Duchess of Beck Princess Ernestine Justine Ernest August Dorothea Louise, Princess-Abbess of Itzehoe Prince Frederick William |
| House | House of Schleswig-Holstein-Sonderburg-Augustenburg |
| Father | Alexander, Duke of Schleswig-Holstein-Sonderburg |
| Mother | Dorothea of Schwarzburg-Sondershausen |
Ernest Günther I of Schleswig-Holstein-Sonderburg-Augustenburg (14 October 1609 – 18 January 1689) was a Duke of Schleswig-Holstein of its Sonderburg line. He was the first to have his ducal seat in Augustenborg Palace, which he built and named in honor of his wife. He ruled from 1647 until his death in 1689.