Who was the leader when the Republic of Hawaii was formed?

The Republic of Hawaii was formed in 1894, and the individual who played a central role in this process was Sanford B. Dole. Following the overthrow of Queen Lili'uokalani, Dole became the president of the new republic. He was a pivotal figure in the transition from a monarchy to a republic, focusing on establishing a government that reflected the interests of the plantation owners and other pro-annexation factions, largely composed of American businessmen. This was a significant shift in Hawaii's governance, moving away from monarchical rule.

The other figures mentioned held important roles in Hawaiian history but were either earlier monarchs or leaders involved in different periods. Queen Lili'uokalani was the last reigning monarch prior to this transition, while Kamehameha V and Kalakaua were earlier kings who ruled during the kingdom's era, long before the establishment of the Republic. Thus, Dole’s leadership at the formation of the Republic of Hawaii distinguishes him as the correct answer.