Who is the “wanderer, harried for years on end" in the Land of the Lotus Eaters?

The wanderer is Odysseus himself.  He has been trying to get home to Ithaca since the Trojan War ended, but he has been "harried for years on end".  This means that he has had troubles for many years.  He was stuck on Calypso's Island, and has faced many obstacles to his journey.  The Lotus-Eaters are one of the obstacles, as the Cyclops and others will be.