Original sentence: "A Visit from St.Just as Dickens shaped Christmas traditions, 19th century cartoonist Thomas Nast gave Santa his familiar form (Harper's Weekly, 1863).Nicholas" ((Sentinel, 1823, authorship by either Major Henry Livingston Jr.or Clement Clarke Moore and popularly known as "The Night Before Christmas") supplied the rotund Santa and his sleigh landing on rooftops on Christmas Eve
Edited sentence: (not Clement Clarke Moore, as was thought until 2000) provided English-speaking countries with their popular images of Santa Claus.Just as Dickens shaped Christmas traditions, Thomas Nast and Major Henry Livingston Jr.Nast's 19th century cartoons gave Santa his familiar form (Harper's Weekly, 1863), while Livingston's poem "A Visit from Saint Nicholas" (Sentinel, 1823, popularly known as "The Night Before Christmas") supplied the rotund Santa and his sleigh landing on rooftops on Christmas Eve