[ANSTHRLD] Name question: Joe the <color>

[Randy Shipp]

Heralds of Ansteorra,

I have a client who has come to me with a name that he's been using
without registration for some time and it falls to me to see if it is
registerable.  It takes the form "GivenName the Color," in this case,
blue.  I am very new to name research, so I'm a bit unsure where to
start with documentation, but I'm skeptical to begin with.  My gut
feeling is that names like Erik the Red (which the client cited as a
precedent for the construction) are references to the person's
complexion or hair color.  And, woad not withstanding, blue isn't
common for either.

What's my best starting point?  This name is, I believe, Irish.

Yours in Service,

--Antoine D'Aubernoun