The Palau Islands were discovered by Spanish Europeans in 1543.
This is a map of Truk Islands:
Operation Hailstone (トラック島空襲 Torakku-tō Kūshū, lit. “the air-strike on Truk Island”) was a large naval, air and surface attack, February 17–18, 1944, as a part of World War II. The United States Navy attacked the Japanese naval and air base in the Truk Islands, a part of the Caroline Islands.
Moen Island and Dublon Island and general sketch map of area of Operation Hailstone.
Map of a portion of southern Dublon Island.
This is the flag of Chuuk Islands: