During his reign, foreign troops participating in the Thirty Years' War began retreating into and quartering in East Frisia.

He reached a settlement with the East Frisian Estates, who them paid him homage, ultimately even the city of Emden did so.

Under his leadership, the Lordships of Esens, Stedesdorf and Wittmund were finally incorporated in the county of East Frisia.

At the age of just 26, he got embroiled in a fight with a lieutenant of the army of general Matthias Gallas, which was quartered in Berum Castle.

Since Rudolf Christian was childless, he was succeeded as Count of East Frisia by his brother Ulrich II.