Wenceslaus I | |
|---|---|
| Duke of Cieszyn | |
 Coat-of-arms of Upper Silesia (Cieszyn, etc.) | |
| Born | 1413/18 |
| Died | 1474 |
| Noble family | Silesian Piasts |
| Spouse(s) | Elisabeth of Brandenburg |
| Father | Boleslaus I, Duke of Cieszyn |
| Mother | Euphemia of Masovia |
Wenceslaus I of Cieszyn (Polish: Wacław I cieszyński, Czech: Václav I. Těšínský, ‹See Tfd›German: Wenzel I. von Teschen; 1413/18 – 1474), was a Duke of Cieszyn from 1431 (until 1442 with his brothers as co-rulers), Duke of half of Bytom during 1431–1452 (returned to him soon after until 1459) and Duke of Siewierz (until 1443).
He was the oldest son of Duke Bolesław I of Cieszyn by his second wife Euphemia, daughter of Duke Siemowit IV of Masovia.