Hawaii was a Kingdom (Kingdom of Hawaiʻi) from 1795 until 1894 and an independent republic from 1894 until August 12 1898. Hawaii was annexed from the United States of America as an overseas U.S. territory in 1898 and became the 50th state in 1959.
Mauna Kea at 4'205 metres is the highest point of the archipelago.
On August 21th 1959, Hawaii was admitted into the Union and became the 50th state.
This airmail stamp issued on same day.