[3] Tubajon, which was once a barangay of Loreto, became a municipality on June 21, 1969, under Republic Act No.

According to local folklore, during the Spanish regime, a banca boarded with Guardia Civils landed in the shores of Tubajon in search of a criminal.

The man answered "Akong Tubajon ang suba aron sayon dakpon ang mga isda" (I will poison the river with Tuba leaves so that the fishes could be easily caught).

However, in February 2010, the Supreme Court ruled that the law was unconstitutional, as the necessary requirements for provincial land area and population were not met.

[5] On October 24, 2012, however, the Supreme Court reversed its ruling, and upheld the constitutionality of RA 9355 and the creation of Dinagat Islands as a province.