Simplify the following text for a Grade 10 native English-speaking person.
Original: Henry William Allingham ( 6 June 1896 â `` 18 July 2009 ) was a British supercentenarian , First World War veteran and , for one month , the verified oldest living man in the world .
Simplified: Henry Allingham ( born London , 6 June 1896 ; died 18 July 2009 ) was a British supercentenarian and First World War veteran .