Harold is from the Old English name Hereweald, derived from the elements here "army" and weald "power, leader, ruler". It was the name of two kings of England. The name fell out of use after the loss of the Battle of Hastings and the Norman Conquest. It was revived in the 19th century.
Harold is cuddly. A sweet teddy bear of a name that makes me think of autumn and cozying up inside with a good book, a hot cup of cocoa, and nice blanket. It is comfort.
I adore the nickname Halley, like Halley's comet. Rollo would be quite cute too!