1. Kamehameha I becomes first ruler of unified Hawaii - On May 19, 1795, Kamehameha I successfully conquered the island of Oahu and became the first ruler of a unified Hawaii.

2. First plantation workers arrive from China - On May 19, 1852, the first group of 153 Chinese contract laborers arrived in Hawaii to work on sugar plantations.

3. Queen Liliuokalani is born - On May 19, 1838, Liliuokalani, the last queen of Hawaii, was born in Honolulu.

4. Pineapple becomes Hawaii's official state fruit - On May 19, 2005, the pineapple was declared Hawaii's official state fruit due to its significance in Hawaii's agriculture industry.

5. Hawaiian language immersion program is established - On May 19, 1987, the Hawaiian Language Immersion Program was established, allowing students to receive their education in the Hawaiian language. This helped to revive and preserve the Hawaiian language and culture.