Henry 'Harry' Albro Williamson (October 25, 1875 - January 3, 1965) was a postal worker and a prolific researcher and writer on the subject of Freemasonry.

He organized the first Lodge of Research in Prince Hall Freemasonry, becoming its first and only Master in 1943.

[4] He filled the role of Grand Secretary for over thirty years.

[1] His papers, consisting of over 1200, items including his Prince Hall Masonic collection were given to the Schomburg Center at New York Public Library in February 1936.

He was born in New Jersey but moved to Oakland California in 1880 when his father died.