Looking for Martens Family

Hi i`m Val i am trying to trace Ernest Augustus Martens my grandfather born 19th July 1860 think he was born in Germany, but where in Germany not sure Schleswig Holstein has been mention, he came to England sometime before 1890 and married my grandmother Fanny Pettengale 9th August 1891 in Battersea, London, my mother told me his family disowned him for comeing to England but would love to know if i have any relatives on my grandfathers side.