Question: When did Janusz Iii Of Masovia's father die?
Sentence (from "Konrad III Rudy"): He was a duke of Czersk, Liw, Warsaw, Nur, Łomża, Ciechanów, Różan, Zakroczym and Wyszogród during 1454-1471 jointly with his brothers (under regency until 1462), Duke of Płock, Wizna, Płońsk and Zawkrze during 1462-1471, and after the division of the paternal domains in 1471, sole ruler over Czersk and Liw, over Wyszogród during 1474-1489 and again in 1495, over Zakroczym since 1484, over Nur since 1488 and over Warsaw since 1489.
Relevant evidence: No