1. On May 28, 1900, Hawaii officially became a territory of the United States following the signing of the Organic Act by President William McKinley. This act established a government for Hawaii and granted citizenship to all Hawaiian residents.

2. In 1934, the first transpacific flight from Hawaii to the mainland United States was completed on May 28. The plane, a Sikorsky S-42 flying boat named "Samoan Clipper," took off from Pearl Harbor and landed in California after a 14-hour flight.

3. On May 28, 1959, a devastating tsunami struck the town of Hilo on the island of Hawaii. The wave, caused by an earthquake in the Aleutian Islands, killed 61 people and caused widespread damage to homes and businesses.

4. May 28, 1961, marked the opening of the Ala Moana Shopping Center in Honolulu, which at the time was the largest shopping center in the world. The mall is now the largest open-air shopping center in the United States.

5. In 2010, President Barack Obama made a historic visit to the Kamehameha Day Parade in Honolulu on May 28. Obama, who was born in Hawaii, became the first sitting U.S. president to attend the parade, which celebrates the life of King Kamehameha I, who united the Hawaiian Islands in 1810.