Katana or Shin Gunto of an Imperial Japanese Army Officer made by the Swordsmith Kishu ju Fujiwara Yasushige. From the structure of the Koshirae and the blade we can affirm that it is a Type 98 model that preserves all its original parts.

Japanese Katana from World War II WW2.

The Koshirae or structure
The scabbard (鞘 Saya) is metallic and is preserved in good condition, although it has lost part of the paint. It has the upper metal part (帯執 Obi-tori) and the lower ornate metallic guard (Ishizuke)
The format of the metallic guard (鍔 Tsuba) is the characteristic solid one of the mid-war period. It contains 8 Seppa, four on each side of the Tsuba.
The opening button (Chuso) is the original one with the shape of a sakura flower and fulfills its function of holding the scabbard.
The braiding (柄糸Tsukaito) of the hilt (柄Tsuka) is of the Morohinerimaki type. The ray skin (鮫Same) inside is preserved in good condition and is white in colour. It also contains the original upper metal piece (頭Kashira) of a smooth shape with the sakura flower as ornamentation. It has a Menuki (目貫) on each side and is the three-flower model corresponding to Type 98.
The ring (Sarute) of the hilt is the simple model.

The Nagasa or blade
We can highlight the following characteristics of the blade:
The overall shape of the blade is Shinogi-zukuri like most shin gunto.
The temple around the cut (刃文Hamon) is of the Sugu type (straight).
The steel pattern of the blade (地肌Jiada) is Muji type (flat or smooth)
The back cut (棟Mune) is Ihori type (single open angle)
On the tang (茎Nakago) you can read the Swordsmith signature (名Mei) and it contains three holes.
The blade is in good condition except for the tip and some rust spots.

The Mei or signature
On the Nakago you can read the Mei, the name of the Swordsmith  Kishu ju Fujiwara Yasushige (紀州住藤原安重).