William Pitt Leleiohoku II, born Kalahoʻolewa (January 10, 1855 – April 9, 1877), was a prince of the Hawaiian Kingdom and member of the reigning House of Kalākaua.

During Kalākaua's trip to the United States to negotiate the Reciprocity Treaty of 1875, Leleiohoku ruled as regent from November 17, 1874, to February 15, 1875.

[6] The youngest surviving child of a large family, his biological siblings included: James Kaliokalani, David Kalākaua, Liliʻuokalani, Anna Kaʻiulani, Kaʻiminaʻauao, and Miriam Likelike.

She renamed him after her deceased first husband High Chief William Pitt Leleiohoku, the son of Prime Minister Kalanimoku.

He carried his purpose into immediate execution by insisting within a week from that time that his sister Ruth should legally adopt as her own my brother Leleiohoku, whom she had taken from his parents at birth.

All the papers were carefully drawn up by the prince, and everything connected with the adoption was made complete, so that in no event could the legality of my brother's position be doubted.

The innocent cause of this disturbance, the child thus adopted by Mrs. Bishop and named Keolaokalani, died in about six months...[16]Leleiohoku was educated at the St. Alban's College established by the Anglican Church of Hawaii in Honolulu.

Founded by Bishop Thomas Nettleship Staley and his assistants Archdeacon George Mason and Reverend Edmund Ibbotson, the school was located in the Pauoa Valley on Oahu.

[26] On January 25, 1873, the new king commissioned Leleiohoku as major of the military staff of the Governor of Oahu under his brother-in-law John Owen Dominis.

To quell the civil disruption, American and British troops were landed from three warships in the harbor with the permission of the Hawaiian government, and the rioters were arrested.

[33] In the absence of legitimate children, Article 22 of the 1864 Constitution gave the monarch the power to appoint a successor or heir with the consent of the House of Nobles.

In later life, Liliʻuokalani admitted that "those of Prince Leleiohoku were really in advance of those of his two sisters, although perhaps this was due to the fact that the singing-club of the regent was far superior to any that we could organize; it consisted in a large degree of the very purest and sweetest male voices to be found amongst the native Hawaiians.

[27] An 1888 military act passed by the legislature reduced the size of the army to four volunteer companies: the Honolulu Rifles, the King's Own, the Queen's Own, the Prince's Own, and the Leleiohoku Guard.

The Hawaiian Gazette, noted that he was "often suffering intense pain, but no fears of any fatal result had been entertained until the day preceding his death, when his symptom became more unfavorable."

[56] Leleiohoku's hānai mother, Keʻelikōlani, wanted to be named heir, but the king's cabinet ministers objected as that would place Bernice Pauahi Bishop, her first cousin, next in line.

[13][59][60][61][62] On June 24, 1910, in a ceremony officiated by his sister Queen Liliʻuokalani, his and his family's remains were transferred to the underground Kalākaua Crypt after the main mausoleum building was converted into a chapel.

[63][64] Leleiohoku's death was greatly mourned by the nation since high hopes and anticipations were placed on him as the future monarch of Hawaii.

[65] The United States Minister to Hawaii Henry A. Peirce commented on Leleiohoku's prospect as ruler: "Of correct morals, well-educated and accomplished, the late prince promised to become, had he lived to ascend the throne, a wise and popular sovereign.

"[55] In 1875, the Hawaiian postal service issued a twelve cent, black on white postage stamp featuring a portrait of Leleiohoku in uniform.

[65][66] Leleiohoku's life was dramatized in Almost a King by local Hawaiian playwright Clarence Waipa, which originally premiered in 1979 as the first act of a trilogy at St. Joseph High School in Hilo.

[70][71] Influenced by Henri Berger, the bandmaster of the Royal Hawaiian Band, Leleiohoku learned from and adapted elements of the folk tunes of visiting merchants, sailors and foreign settlers of Hawaii into his compositions.

One of his composition "Kāua I Ka Huahuaʻi" was adapted by Johnny Noble into the popular American song, "Hawaiian War Chant".

Our poems and musical compositions were repeated from one to another, were sung by our friends in the sweetest rivalry, and their respective merits extolled: but candor compels me to acknowledge that those of Prince Leleiohoku were really in advance of those of his two sisters, although perhaps this was due to the fact that the singing-club of the regent was far superior to any that we could organize; it consisted in a large degree of the very purest and sweetest male voices to be found amongst the native Hawaiians.