In Irish mythology, Donn was the Lord of the Dead and father of Diarmuid Ua Duibhne. He gave his son to be nurtured by Aengus Og.
Donn is also referred to as the Dark One and in modern Irish the word for the colour brown is donn. Donn is regarded as the father of the irish race a similar position that Caesar noticed among the Gauls with Dis Pater.
