Boston area 1890 to1820

[suzyf]

 In 1893,my g grandfather,John Clark(e) age 33,weaver together with his brother William,age 37 arrived on The City of New York intended destination Boston .Both were born in Nottingham .John Clark didn't bother to come back till 1916 ? His ship was attacked and he was too injured to disembark so he was shipped back and family legend says he is buried in Boston.
What might it be possible to find out about these 2 and where do I start?.I'm assuming William stayed in US as somebody informed John's wife that he'd died.
(She then married the man she'd lived with for many years)
Any suggestions?