Children of the House of Cleves describes and analyses the lives of Sybylla, Anna, Wilhelm and Amalia, the children of Johann III, Duke of Cleves. Though their parents were staunch Catholics, Wilhelm of Jülich‑Cleves‑Berg was a Lutheran – when it suited him. He challenged the Holy Roman Emperor, Charles V, over the strategically important Duchy of Guelders. He believed that France would support him, but Francis I left him defenceless and Guelders became part of the Habsburg Netherlands. Sybylla became the Electress consort by marriage to electoral Prince Johann Friedrich of Saxony. He would be captured during the Schmalkaldic War, and Sybylla defended the city of Wittenberg under siege during his absence. Both she and her husband were passionate supporters of the Reformation. Amalia was considered as a possible bride for Henry VIII before he chose her sister Anna. She was a great lover of music and poetry, with her own poems recorded in a song book. These four children had an illustrious lineage – descended from both the kings of England and France and closely related to Louis XII and the dukes of Burgundy. Their various trials and triumphs illuminate the convulsions of sixteenth‑century continental and Tudor politics and the spiritual and civic revolution that was the Reformation. It began in the German states, and these four lives were intimately involved in it. Based upon primary documentary sources, Children of the House of Cleves explains what motivated or caused some of the largest wars in continental Europe in the run‑up to the Thirty Years War in Germany, a time of massive religious and political strife.