Muhammad
Muhammad's life is traditionally defined into two periods: pre-hijra (emigration) in Mecca (from 570 to 622), and post-hijra in Medina (from 622 until 632). Muhammad is said to have had thirteen wives in total (although two have ambiguous accounts, Rayhana bint Zayd and Maria al-Qibtiyya, as wife or concubine.) Eleven of the thirteen marriages occurred after the migration to Medina.
Year of Sorrow
Khadija, Muhammad's first and only wife for the 25 years up to her death, died in 619 CE when she was about 65 years old. Muhammad was almost 50 at this time, and the death happened not long after the end of the boycott against Muhammad's clan. The boycott prohibited, among other things, trade with Muhammad's family. The food shortage that it caused probably contributed towards Khadija's death.