| Tanah Merah | |
| Settlement Type: | Town |
| Pushpin Map: | Indonesia South Papua#Indonesia Western New Guinea |
| Pushpin Label Position: | bottom |
| Pushpin Map Caption: | Location of Tanah Merah in Boven Digoel, South Papua##Location of Tanah Merah in Indonesian Papua |
| Coordinates: | -6.0967°N 140.3033°W |
| Subdivision Type: | Country |
| Subdivision Name: |  Indonesia |
| Subdivision Type1: | Province |
| Subdivision Type2: | Regency |
| Subdivision Name1: | South Papua |
| Subdivision Name2: | Boven Digoel Regency |
Tanah Merah (or Tanamerah, which means Red Land) is a town in the South Papua province of Indonesia (not to be confused with Tanahmerah Bay) on the bank of Digul River, located some two hundred miles from Merauke within the interior of Western New Guinea (a town not occupied by the Japanese during WWII). It is the administrative center of Boven Digoel Regency.
The town acted as a Dutch penal colony during the period when Indonesia was a Dutch colony.
Under Indische Staatsregeling Article 37, "those who can be considered by the Government to disturb or have disturbed the public peace and order will be without any legal proceedings exiled for an indefinite period to a specially appointed place" were sent to Tanahmerah. Dr. Sutan Sjahrir, first prime minister of the Indonesian Republic, described the political prisoners thus exiled as being in "profound spiritual misery" and "permanently broken in spirit".
In 1942, the Netherlands East Indies government-in-exile (in Australia), fearing partisan armies, which would prejudice the postwar reimposition of Dutch colonial rule in the Indies, organised for the prisoners to be brought to Australia, to be interned as prisoners of war. This did not fit entirely well with the host country, and on 7 December 1943, the Tanah Merah prisoners were freed from their Australian prison camps.
Lockwood (1975) considers the evacuation of these prisoners to Australia (and their subsequent freedom within Australia) to be a vital catalyst in the launching of the boycott on Dutch shipping (the Black Armada) at the end of the second world war and in the subsequent creation of the Republic of Indonesia.
The town is served by Tanah Merah Airport.