Iwami Province was in the Sanin Region, an area encompassing provinces in the western portion of Honshū along the Sea of Japan.

In current terms, Iwami Province corresponds to the western portion of Shimane Prefecture.  The province was comprised of six districts, including Ano, Nima, Naka, Ōchi, Mino, and Kanoashi. The province was elongated from east to west, with the city of Ōda the center of the eastern portion, the cities of Gōtsu and Hamada in the central portion, and the city of Masuda in the western portion.  Iwami was traversed by the Gō River, which is the only river that crosses the mountainous area of the Chūgoku Region.

The provincial capital was in the city of Hamada in the Naka District.  Iwami maintained close ties to Aki Province. Provincial temples and convents were located in Hamada.

During the Sengoku period, clans fought for control of the Iwami-Ginzan Silver Mine as an important source of revenue to fund their campaigns.  Iwami was also known as the source of sekishū gawara, or a form of clay bricks used widely for construction, including of national temples.

Shugo:

1467-1477:  Yamana Masakiyo

1481-1495:  Ōuchi Masahiro

1495-1528:  Ōuchi Yoshioki

1528-1551:  Ōuchi Yoshitaka

Sengoku daimyō:

• Amago clan
• Mōri clan
• Ogasawara clan

Shrines:

The Mononobe Shrine located in the city of Ōda is an ichi-no-miya, or shrine of the highest status in the region based on rankings established by the Imperial Court.

The Tabato Shrine located in the city of Gōtsu is a ni-no-miya, or shrine of the second rank.

The Ōmatsuri Ame-no-Iwa Tohiko Shrine located in the city of Hamada is a san-no-miya, or shrine of the third rank.