In 855 Athelwulf went on a to Rome. He took his youngest son Alfred with him. He left the kingdom in the care of Athelbald, his second son. After spending a year in Rome he traveled to the court of Charles the Bald, King of the West Franks. There he spent the summer and fall of 856. In October 856 he wed the king's young daughter, Judith. She could not have been any older than thirteen at the time. The marriage was at best a diplomatic alliance. Both men were suffering from Viking attacks, and formed a common alliance. Charles insisted that his daughter be queen. When Athelwulf returned to Wessex there was opposition to his remaining king. To avoid a civil war he agreed to take the sub-kingship of Kent, held by Ethelbald. He let Ethelbald become king of Wessex. Athelwulf died in 858 as the King of Kent. Ethelbald took his father's young wife Judith as his own wife, apparently without a major scandal.