Welcome to Harry Potter Theory. Today we’re discussing the history and family tree of the Black family.
You might not know this, but Sirius Black was more than just a powerful wizard who escaped the dungeons of Azkaban.
By birthright, he was a member of one of the most powerful wizarding families in all of Britain.  In fact, the Black family line can be traced back through the centuries, and was celebrated as one of the proudest pure-blood families in the world.
And by the time Sirius was born, he was one of the few male heirs that remained.  Which meant his passing, in the Death Chamber on the ninth level of the ministry of magic, marked the end of the Black Family line.  
But even that wasn’t really the end for them.  Although the women of the family didn’t typically keep their last name after marriage, they married into dozens of other pure blood families throughout England.  In some way, almost every Weasly, Potter, Lestrange, Lupin, and Malfoy could find a connection to the Blacks.
Today, we’re going to take a look at the very first recorded ancestor in Sirius’s line, and trace the history of the Black family, from Sirius’s own namesake, to the final male heirs.