The story is based on a novel by award-winning writer Sato Kenichi, which was published in 2006.
Plot of the series: In this altered edition of Japan’s history, Oda Nobuhide never had a second son but a daughter, who is still being raised as his heir and successor.
More information: http://mydramalist.com/6908-onna-nobunaga
Note: Each episode is around 2 hours long, so that's why the filesize for each episode is quite large.