Maria Serena Encarnacion Icasiano Diokno, (born August 16, 1954) also known as Maris,[1] is a Filipino historian, academic, and former government official best known[2] for having served as chair of the National Historical Commission of the Philippines (NHCP)[3] and as a high-ranking official of the University of the Philippines (UP) system.

[5][better source needed] She resigned from her position on November 29, 2016, in response to the burial of former president Ferdinand Marcos at the Libingan ng mga Bayani in Taguig, Metro Manila.

[6] She is the daughter of Filipino nationalist figure and legislator Sen. Jose W. Diokno, who is the father of human rights.

Diokno is also a descendant of William Boleyn, who is grandfather to Elizabeth I of England, and Diokno could trace her roots through the Fitzgerald clan all the way back to the first century A.D.[7][9] Maris has taught history, focusing on Asian and Southeast Asian history.

Her expertise in national history is primarily centered on the Philippine Revolution and on the Philippine-American War, of which her great-grandfather Ananías took part in as Governor of Capiz and the first general of the navy.