That's right metz - the song was called I Believe in Father Christmas
Lake wrote this as an objection to the commercialism of Christmas. He was concerned that the true spirit of Christmas was being lost in the marketing of the holiday.
Lake was the lead singer and guitarist for Emerson, Lake And Palmer. This was his only hit as a solo artist.
The part at the end is based on "Lieutenant Kije Suite" by Russian composer Sergei Prokofiev. Keith Emerson came up with the idea to use it.
Pete Sinfield, who wrote lyrics for many Emerson, Lake And Palmer songs, helped write this.
Lake was surprised this was a hit. Many people misinterpreted it as an anti-religious song, and he thought it wouldn't go over well as a single.
Lake (from Mojo magazine): "I find it appalling when people say it's politically incorrect to talk about Christmas, you've got to talk about 'The Holiday Season.' Christmas was a time of family warmth and love. There was a feeling of forgiveness, acceptance. And I do believe in Father Christmas."