Johan Rantzau
| Johan Rantzau | |
|---|---|
| Born | 12 November 1492 Steinburg, Duchy of Holstein | 
| Died | 12 December 1565 (aged 73) Itzehoe, Duchy of Holstein | 
| Buried | |
| Allegiance | Christian III | 
| Service | Royal Danish Army | 
| Rank | Field marshal | 
| Battles / wars | 
 | 
| Spouse(s) | Anna Walstrop (m. 1554) | 
| Children | Heinrich Rantzau | 
Johan Rantzau (12 November 1492 – 12 December 1565) was a German-Danish field marshal and statesman known for his role in the Count's Feud. His military leadership ensured the succession of Christian III to the throne, which brought about the Reformation in Denmark.