Magenta Black, née Tripe(1808-1871) was the wife of Licorus Black and one of the earliest known Black family members.
Magenta got accepted into Hogwarts school of Witchcraft and Wizardry in 1819 and was made a Prefect in 1823. In that year she met and fell in love with Licorus Black. His family didn't approve of her but he chose her anyways. The two married the moment they passed their N.E.W.T's as she was pregnant with their eldest child Misapinoa (1826). The pair got two more children: Cygnus Black I (1829) and Arcturus Black I (1835).
Magenta raised her children with distance and strong belief in their worth as pure-bloods. It is said she greatly approved of her daughters marriage to Jimbo Blishwick.
She died of dragonpox in 1871.