In 1887, he was appointed ambassador to Great Britain, with the rank of envoy extraordinary and minister plenipotentiary to the Court of St James's, and accompanied Queen Kapiʻolani and Princess Liliʻuokalani to the celebration of Queen Victoria's Golden Jubilee. The diplomatic party also included Governor John Owen Dominis, husband of the princess, Colonel James Harbottle Boyd, secretary and attaché to Iaukea, and their attendants. On the journey across the United States, they visited Washington, DC and met with President Grover Cleveland. The Hawaiian party was graciously received during the Jubilee and given the same honor as every nation in attendance. Iaukea translated for Queen Kapiʻolani, who spoke only Hawaiian, during her official audience with Queen Victoria.