President Cleveland reused to annex the territory of Hawaii because he believed the white settlers and land owners had unconstitutionally and unjustly deposed the popular Queen Liliukalani of Hawaii.
Hawaii had already been recognized as an independent Kingdom during the time of President Tyler. The kingdom operated numerous consulates around the world and had treaties with over 90 nations.
However, the local population of plantation owners became increasingly powerful and demanded the right to intervene in government policies.
Most of the plantation owners were Americans but were also supported by a small group of local rebels who wanted to overthrow the monarch.
Eventually, the Queen was deposed in a coup and the United States Navy was called in to control the situation.