Complex sentence: The poem first appeared in the Newry Telegraph on 19 April 1817, and was re-printed in many other periodicals, but was forgotten until after his death when Lord Byron (George Gordon Byron) drew the attention of the public to it.
Split into simpler sentences: The poem first appeared in the Newry Telegraph, April 19,1817, and was re-printed in many other periodicals. But it was forgotten until after his death when Lord Byron drew the attention of the public to it.