A Spanish missionary expedition commanded by Sargento Mayor Francisco Padilla arrived on Sonsorol on 30 November 1710, coming from Manila aboard the patache Santísima Trinidad.

[4] In 1899 Spain decided to sell the islands to the German Empire, which lost control over the territory in World War I, when Japan took over.

The United States took possession of the area at the end of World War II and controlled it until Palau's independence.

During December 2012, the state suffered severely from Typhoon Bopha and people were evacuated to Arakabesang in Koror.

A couple of months later, and due to a government decision, only Sonsorol was re-inhabited, as it cheaper and closer to get to and send supplies to.

Sonsorol Island, also called Dongosaro or Dongosaru, is encircled by a coral reef extending 160 to 480 metres (520 to 1,570 ft) offshore.

Sonsorol was probably the first of Palau Islands visited by a European - the Jesuit expedition of Francisco Padilla on 30 November 1710.

A year after Typhoon Bopha, the Palau government issued a reconstruction plan for the island, and also built a small dock there.

Pulo Anna or Puro is fringed by a coral reef extending beyond 460 metres (1,510 ft) offshore.