Wizards, Witches and Beings: I
Imago, Inigo 
Author of The Dream Oracle, a text that Trelawney uses in her fifth year Divination classes (OP).
Inigo=Medieval Spanish form of Ignatius; the name of a famous seventeenth
century British architect. Ignatius is derived from 'Ignis,' the Latin word
for fire).
Imago=Latin for image, likeness (i.e.:, a picture, statue, mask, an
apparition, ghost, phantom).
Ingolfr the Iambic 
Norwegian poet of the 1400s whose verse includes references to Quidditch (QA8).
Ivanova 
Most likely a witch, since her surname has a feminine ending in a a part of the world where surnames are modified by gender.
