Hello all.
I recently acquired a sword (this is my first) that is signed by Bishu Osafune Norimitsu. The date is either 1446 or 1447 during the Muromachi period and has a certificate of authenticity from NBTHK.
I am wondering what the grade/rank of the sword is and any information regarding Bishu Osafune Norimitsu. My understanding of some research is that Bishu Osafune is the location and school and Norimitsu is the person. I however can't find which Norimitsu made this blade and what the historical significance is. Please, even any amount of information (so that I can document this blade) would be helpful to me.
Thank you everyone.
I am making a post in this subsection because I am seeking general information. I've uploaded the certificate to this thread. I originally made a translation post here, with more pictures of resources that I cannot read: