Morgan William II O'Donovan CB, DL (1861–1940), The O'Donovan, and assumed the designation of The O'Donovan from 1890 to his death in 1940. He was the son of Henry Winthrop O'Donovan, The O'Donovan, and Amelia O'Grady, daughter of Gerald de Courcy O'Grady, The O'Grady, and Anne Wise. O'Donovan was a descendant of Donal II O'Donovan, The O'Donovan of Clancahill, the last such to be formally inaugurated in the ancient Gaelic manner, with the White Rod, by the MacCarthy Reagh, Prince of Carbery.
O'Donovan graduated from Magdalen College with a Bachelor of Arts. His first civic office, following his accession to the chiefship, was that of High Sheriff of County Cork in 1892.
He was an officer in the 3rd (Militia) Battalion of the Royal Munster Fusiliers (until 1881 known as the South Cork Light Infantry), where he was appointed major on 4 December 1891. Following the outbreak of the Second Boer War in October 1899, the battalion was embodied in December 1899, and embarked the SS Sumatra for South Africa on 23 February 1900. From arrival in March 1900 until 1902, he took part in operations in the Transvaal, Orange River Colony, and Cape Colony, and was mentioned in despatches. From 1903 to 1914 O'Donovan was Colonel of the 4th Battalion (Extra Reserve), Royal Munster Fusiliers.