I have to admit, I always thought of Catwoman as the Michelle Pfeiffer type, so I was rather shock when I read Year One, and saw that she actually had very short black hair.
The short hair is a relatively recent approach, first seen in Year One
and later used in the animated The New Batman Adventures
and in Darwyn Cooke's modern redesign. But Selina Kyle has always been a brunette in the comics, except for one 1946 issue (before her real name was revealed) where she was a redhead. And all three Catwomen in the '60s series/movie were brunettes, although Julie Newmar's hair color varied from appearance to appearance and she bordered on blonde
once or twice.
So the blonde Pfeiffer playing Catwoman was a major departure. Batman: The Animated Series
originally intended to do a brunette Catwoman but was obligated to make her blonde (and Penguin a deformed mutant) because of pressure to conform to what Burton was doing in the movies. But those two are the only blonde Catwomen as far as I know. When they came back for TNBA, that pressure was gone and they were able to restore the more classic designs for Catwoman and Penguin that they'd originally wanted to use. (There was an issue of the tie-in comic to the TV continuity that explained how Catwoman learned that animals were being exploited by a cosmetics company and resolved to stop dyeing her hair blonde.)
EDIT: No, wait, I did find images of a blonde Catwoman from issues published in 1946-7: http://www.batman-online.com/forum/i...hp?topic=32.30
So it was done before Pfeiffer, but only briefly.