HONOLULU, Dec 12 (AFP) - A Hawaiian princess dubbed the island chain's last remaining royal, has died, the palace announced Monday.

Abigail Kawananakoa had no formal title, but was part of a family of nobles whose predecessors ruled Hawaii until their overthrow by commercial settlers at the end of the 19th century.

The heiress, referred to by some on the island as the "last alii" -- the Hawaiian word for "royal" -- died on Sunday, according to a statement issued by the Iolani Palace, the historic home of the family.

"Hawai‘i mourns the loss of HRH Princess Abigail Kinoiki Kekaulike Kawananakoa, who died peacefully last evening at her Nu‘uanu home with her wife Veronica Gail Kawānanakoa at her side," the statement said.

"'Abigail will be remembered for her love of Hawai‘i and its people,' said Veronica, 'and I will miss her with all of my heart.'"

No cause of death was given for the 96-year old, but the Hawaii News Now website noted she had been struggling with poor health.

Hawaii governor Josh Green ordered flags to be flown at half staff until Sunday evening.

"(My wife) Jamie and I are deeply saddened by the loss of Princess Abigail Kinoiki Kekaulike Kawananakoa," Green said.

"Abigail bore the weight of her position with dignity and humility, enriched the lives of everyone she touched, and like so many Aliʻi who came before her, she has left a legacy dedicated to her people in perpetuity."

Abigail, the great-granddaughter of an Irish businessman whose Hawaiian sugar plantations made him fabulously wealthy, was adopted into the royal lineage at the age of five, more than three decades after the royal family was deposed.

The archipelago of Hawaii was home to a series of independent chiefdoms until being unified into a single kingdom in the early 19th century under the Kamehameha dynasty.

It traded independently with other sovereign nations until its annexation and occupation in 1898 by the United States.

Hawaii became the 50th state admitted to the union of the United States in 1959.

Abigail's lineage branches off before Kamehameha came to the throne in 1810.

A separate offshoot of the Kamehameha dynasty, which stresses the notion of primogeniture, proclaims Princess Owana Kaʻohelelani head of the modern-day royal family.