When his oldest brother Charles Ferdinand died in 1669, Christian Ulrich inherited the Duchy of Bernstadt.

When his older brother Silvius II Frederick died in 1697, Christian Ulrich inherited the Duchy of Oels, Christian Ulrich kept the Duchies of Oels and Dobroszyce with Międzybórz and parts of Trebnitz and transferred Bernstadt to his nephew Charles.

In 1698, Christian Ulrich built a ducal crypt as an extension of Castle Church of St. John.

Between 1685 and 1692, he constructed a baroque castle at Neudorf, which he named Sibyllenort, after his second wife, Marie Sibylle of Saxe-Merseburg.

With her he had seven more children: He concluded his third marriage, on 4 February 1695 in Hamburg with Sophie Wilhelmine of East Frisia (born: 17 October 1659; died: 4 February 1698), daughter of Prince Enno Louis Cirksena of East Frisia and Juliana Sophia Justina of Barby-Mühlingen.