what is the background of this film?
Inspired by the flip books his son brought home, McCay said he "came to see the possibility of making moving pictures" of his cartoons.
The Sinking of the Lusitania
Inspired by the flip books his son brought home, McCay said he "came to see the possibility of making moving pictures" of his cartoons. 
what is the sinking of the lusitania? An American silent animated short film by cartoonist Winsor McCay.
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The Sinking of the Lusitania [SEP] Background
His first animated film, "Little Nemo" (1911), was composed of four thousand drawings on rice paper. His next film, "How a Mosquito Operates" (1912), naturalistically shows a giant mosquito draw blood from a sleeping man until it burst. McCay followed this with a film that became an interactive part of his vaudeville shows: in "Gertie the Dinosaur" (1914), McCay commanded his animated dinosaur with a whip on stage. The British liner RMS "Lusitania" briefly held the record for largest passenger ship upon its completion in 1906. McCay displayed a fondness for it, and featured it in the episode for September 28, 1907, of his comic strip "Dream of the Rarebit Fiend", and again in the episode for November 10, 1908, of "A Pilgrim's Progress by Mister Bunion", where Bunion declares it "the monster boat that has smashed the record".