William I of Württemberg
On 24 January 1816, in Saint Petersburg, he married his first cousin, Grand Duchess Catherine Pavlovna of Russia (1788–1819), daughter of Emperor Paul I of Russia (1754–1801) and Princess Sophie Dorothea of Württemberg (1759–1828). The couple had two children:
Philip I, Duke of Pomerania
On 27 February 1536 Philip married Maria of Saxony, the half-sister of Elector John Frederick I of Saxony. In April 1536 in Frankfurt am Main, he and Barnim then joined the Schmalkaldic League. In 1547, after the Protestants had been defeated in the Schmalkaldic War, Philip feared persecution by the enraged Emperor Charles V. He managed to soothe Charles by paying a fine. The changing circumstances made work increasingly hard for bishop Suawe and in 1549, he resigned. He was succeeded by a Catholic bishop, who tried to restore the old situation and make the Church of Pomerania part of the Roman Catholic Church again. The attempt failed, and to ensure independence of his church, Philip appointed his eldest son John Frederick as bishop of Cammin. He also revived Bugenhagen's church order and mediated in the theological disputes that raged in his duchy.