This is a scarf that probably Carson would wear when he is off duty at Downton Abbey. The scarf is a type of Gansey knit pattern, so the needle size and yarn show the stitch definition.

It is designed in 3 sections (A, B and C), with the ends being different but coordinating knit/purl patterns. The knitter can combine the patterns to have both ends the same. So this pattern is really 3 patterns-in-one (AA, AC, or CC)! B is a k2p2 ribbing section.
The scarf is started Channel Island Cast-On (with a link to the You Tube video showing demonstrating the technique.
To have both ends identical, the opposite side is also a Channel Island Cast-On and then a Garter Stitch Kitchener stitch to join with the body of the scarf. There is also a You-Tube video link for this technique.