Herzogtum Schweidnitz-Jauer
In 1286 Bolko I again inherited Lwówek from his brother and in 1291 further enlarged his territories by receiving Świdnica and Ziębice from his elder brother Henry V of Legnica. These territories had formed the southern part of the Duchy of Silesia-Wrocław, which Henry V had acquired upon the death of his cousin Duke Henry IV Probus the year before. Henry V, though backed by King Wenceslaus II of Bohemia, was in need for support to retain his Wrocław acquisitions against the claims of rivalling Duke Henry III of Głogów. From 1288 Bolko I had a new residence erected at Książ Castle in the Świdnica lands. For a brief period, his duchy is sometimes known as the Duchy of Jawor-Świdnica.