On May 10, 1869 Peirce was appointed U.S. Minister to Hawaiian Islands, and confirmed by the U.S. Senate on December 21, 1869. This time he traveled on the transcontinental railroad and arrived in Honolulu by June 15, 1869, twenty years after his last visit. On July 19, 1869 he presented his credentials at the court of King Kamehameha V. When this last ruler of the House of Kamehameha died on December 11, 1872 without naming a successor, the Kingdom faced a political crisis. The popular King Lunalilo then died on February 3, 1874, again with no successor, and the crisis deepened when King Kalākaua was elected by the legislature. Supporters of Queen Emma of Hawaii who was popular with the people, started to riot. At the request of C. R. Bishop who was Minister of the Interior, Peirce called out American troops from the sloops and .