The person who actually coined the term Winterval has been in touch with Andy Mabbett:

I am continually fascinated that the term Winterval, ever caused (and still does) such a furore.

Quite simply, as Head of events at that time, we needed a vehicle which could cover the marketing of a whole season of events – Diwali (festival of Lights), Christmas lights switch on, BBC Children in Need, Aston Hall by Candlelight, Chinese New year, New Years eve etc. Also a season that included theatre shows and open air ice rink, Frankfurt open air Christmas market and the Christmas seasonal retail offer. Christmas, called Christmas! and its celebration, lay at the heart of Winterval.

Political correctness was never the reasoning behind Winterval, but yes it was intended to be inclusive (which is no bad thing to my mind) and a brand to which other initiatives could be developed as part of The Winterval offer in order to sell the City at a time when all cities are competing against each other for the seasonal trade.

Read the rest of his explanation on Andy’s blog!