Marwan ibn al-Hakam was the fourth Ummayad Caliph, who took over the dynasty after Muawiya II gave up the title in 684. Marwan's ascension pointed to a shift in the lineage of the Umayyad dynasty from descendants of Abu Sufyan to those of Hakam, both of whom were grandsons of Umayya (for whom the Umayyad dynasty is named). Hakam was a first cousin of Uthman ibn Affan. Muhammad sent both him and his father, Hakam ibn al-Aas to exile, saying they should never return. Wikipedia
The definitive Wikipedia entry for Marwan I. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Marwan_I
