Prince Wladysław Dominik Zasławski-Ostrogski (ca. 1616 – 1656) was a Polish nobleman (szlachcic) of Ruthenian stock. Prince of The Princely Houses of Poland, Ostroh Ordynat, Grand Koniuszy of The Crown.

Zasławski was the mightiest magnate in Volhynia at that time. He was voivode of Sandomierz Voivodship from 1645 and voivode of Krakow Voivodship from 1649. Starosta of Lutsk 1639-1653, regimentarz of the Crown 1648, second richest, after Stanisław Lubomirski, Polish magnate.

Thanks to chancellor Jerzy Ossoliński elected on Convocation sejm as a one of three regimentarz of the pospolite ruszenie during the Battle of Pyliavtsi in 1648. Because of his incompetence as a main regimentarz the battle were lost. In 1651 he participated in the Battle of Beresteczko. During the Swedish invasion ("The Deluge") was loyal to the king John Casimir Vasa, he prepared the defence of Przemysl.

Since the third decade of 17th century his barony was Stare Selo near Lviv. There he started to build fortress in 1642, which was destroyed during the siege of Lviv in 1648 by the Cossac uprisers of Bohdan Khmelnytsky. Castle was rebuilt in years 1649-1654, inside the fortress was built a palace.

Marriage and issue

Władysław Dominik married Zofia Prudencja Ligęza h. Półkozic in 1634 and Katarzyna Sobieska h. Janina, daughter of Jakub Sobieski voivode of the Ruthenian Voivodeship and sister of King Jan III Sobieski, in 1650 and had two children:

• Aleksander Janusz Zasławski (1650-1682), unmarried
• Teofilia Ludwika Zasławska (1654-1709), married Prince Dymitr Jerzy Wiśniowiecki and later Józef Karol Lubomirski