He was foster-brother and chief advisor to Hugh O'Neill, Earl of Tyrone during the Irish Nine Years' War.
He had five siblings – John, Peter, Richard, Walter and Joanne, all born and raised in Ireland – of which Henry was the youngest son.
[13] Sometime after 1558, young brothers Hugh and Brian, grandsons of Irish Gaelic nobleman Conn O'Neill,[c] were moved into the Hovenden family's care.
[16] To this end, Giles acquired the lease to a property in Balgriffin formerly belonging to Conn, via an arrangement made with the Crown.
[27] Tyrone's mercenary forces, commanded by his Hovenden foster-brothers, proceeded to Inishowen upon hearing of the presence of Spanish fugitives there.
[32] On 14 September 1588, writing from Dungannon, Henry Hovenden reported to FitzWilliam that "they with 150 men attacked the Spaniards at Illagh, the O'Docartaig town, and the second day took them prisoners.
[3] Around 1596, Henry Hovenden was ostensibly sent to assist military leader Hugh Roe O'Donnell in pacifying Connacht, however the state intercepted a letter which boasted that "all the delays that could possibly be used for prolonging the causes here have not been omitted".
On 7 December 1597, Walter was killed in battle by the Irish forces of rebel leaders Owny MacRory O'More and Richard Tyrrell.
[39][40] It is highly likely that Hovenden drafted O'Neill's public proclamation of 5 November 1599, which included a list of 22 proposed terms for a peace agreement to Queen Elizabeth I.