[...The finding of the remains of the saint in 1853 afforded striking confirmation of an incident recorded by a Spanish Benedictine named Haedo, who published a topography of Algeria in 1612....]
According to the above text and searches at Google.com, Haedo is indeed Spanish, but rare as a firstname. It is really Basque, though, especially used as a placename. Aedo is a variant and is apart from a placename also used quite a lot as a surname, more than Haedo.
Well, Basque names can be quite difficult, but on the other hand, the Basque are a Celtic people and i've found a site about the names Aedo and Aedho being used in Ulster (nowadays Northern Ireland).
[...The problem of translating Gaelic spellings into English is illustrated by the Gaelic word for Hugh. Aedh is the most common Gaelic spelling in the Annals of the Four Masters and the Annals of Ulster. Aodh is used rarely in the Annals, but more frequently elsewhere. Variations in the Annals of Ulster include Aed, Aeda, Aedha, Aedho, and Aedo. Variations found elsewhere include include Aodha and Aoidh. For a more comprehnsive collection of possible variations, see Hugh McGoughs in History....]
the above text is taken from the link. Note: Aedh is a Gaelic spelling of Hugh, so the Basque Aedo is thus the same as Hugh.