The first attested presence of the young heir of Legnica-Brieg was in 1329, when he, alongside his father, paid homage to King John of Luxemburg, his uncle, husband of his maternal aunt Elisabeth.

Together with his second wife, Katharina Šubić, Bolesław III retired to the small towns of Brieg and Oława, where he retained residences.

Louis convince his older brother to ceded him the overlordship of Legnica in exchange for the towns of Złotoryja, Chojnów, Chocianów and Lubin (Lüben).

Wenceslaus claimed all the inheritance of Legnica; in exchange, he promised to name Louis as his sole heir, even if his unborn child was a son.

The situation remained in an unstable peace until the death of Bolesław III (21 April 1352), which resulted in a civil war between the brothers.

Despite attempts at mediation by Duke Konrad I of Oleśnica, Przecław von Pogarell, Bishop of Wroclaw, and Emperor Charles IV, the war continued for six years, during which time both sides won and lost advantage.

In February 1348, Wenceslaus was part of the entourage who accompanied Emperor Charles IV, when he traveled to Bautzen in order to arrange a meeting with Frederick II, Margrave of Meissen and Landgrave of Thuringia with the purpose of settling their frontier disputes.

In an effort to manage this debt, Wenceslaus was forced to rent out large portions of his duchy to neighboring princes and bishops, and even ordinary knights and townspeople.

Despite the disastrous financial situation of Legnica, Wenceslaus embarked upon several costly ventures, in an effort to raise the prestige of the Duchy, and himself.