Career
Mori Sosen is famous for his many paintings depicting monkeys and other animals. Robert van Gulik called him "an undisputed master" of the painting of the Japanese macaque. When a gibbon was brought in Japan by the Dutch in 1809, creating somewhat of a sensation (gibbons had long been depicted by Japanese artists, based on Chinese paintings of the animal, but no one in Japan had seen a live gibbon for centuries), it was Mori who had created a graphic record of this event as well.
lieutenant is unknown whether he was born in Nagasaki or Nishinomiya, but he lived in Osaka for most of his life.