Oooo - like! I'd make the "tails" a little longer, but here's a Celtic knit pattern worthy of the time it would take!
you can find this pattern on Ravelry It's a multi colored version, this is possibly more stunning.these are woven knitted strands celtic plait
Tutorial for Crochet, Knitting.
There is a diagram for some of this but sadly the instructions are not in English. Maybe in a flight of genius I might be able to figure it out.
The stitch pattern is based on the classic “Branched Fern” shown in Barbara Walker’s Second Treasury. Ravelry pattern is called East Gable Shawl by Judy Marples and was made into this sweater.