Besides the case of his accession above, O'Donovan is first noted in 1586 for burning to the ground the newly built house of the Protestant
Bishop of Cork, Cloyne and Ross,
William Lyon. Not only was the new house rather ostentatious, but Lyon was also accused of stealing and selling priceless gold and silver artifacts from the early period of the church. It is possible, however, that O'Donovan was guilty of burning the whole town of Ross or
Rosscarbery itself, and his men may have slain one of Lyon's daughters in the attack. According to Lyon himself in 1615 nearly thirty years after the incident: Although not among the major figures of his time, Donal II was in their company and active in
Munster affairs during the
Nine Years' War, being one of the few southern lords to support
Hugh O'Neill. In March 1599 pledges of loyalty to the English Crown were received from all the lords in Carbery except for O'Donovan and some MacCarthys, and because of this
Sir Thomas Norris "... caused their castles and houses to be taken and razed, and their people and lands to be spoiled", as he wrote to the
Privy Council. wisely because those who refused had their lands wasted. In late 1599 Donal joined
Florence MacCarthy, whom O'Neill was acknowledging the MacCarthy Mór and
King of Desmond, and
Owen Mac Egan in O'Neill's camp at
Inniscarra near
Cork city, in writing an appeal to Donogh Moyle MacCarthy, one of Owen MacCarthy Reagh's sons and thus O'Donovan's brother-in-law, to join them. The letter was intercepted, and for his part and signature Donal's people were "pacified" savagely by the English forces under the command of Captain George Flower, who related: According to
Philip O'Sullivan Beare, he was one of the principal men of the relief army led by
Donal Cam O'Sullivan Beare (slayer of his brother Diarmaid) to support
Pedro de Zubiaur at
Castlehaven in early December 1601, which led to what was according to O'Sullivan Beare a small but spectacular victory for the Spaniards and Irish: However the English also claimed victory and moderns scholars are very divided on who should be considered the winners. Two months later, an apparently poorly informed or otherwise motivated
Sir George Carew wrote to the English government on 15 February 1602: in Tudor times But this was only true in the sense that they were not all present at the final
Battle of Kinsale itself in late December/early January, almost a month after Castlehaven, although apparently O'Donovan made an appearance (on the Irish side) earlier during the siege. Changing allegiance after this ruinous event, O'Donovan joined Owen's sons Finghin and Donogh Maol, and O'Driscoll, in siding with the English, and O'Sullivan Beare wasted the territory of Clancahill after hearing of it. A surprising event occurred shortly after when some of O'Donovan's men, under the command of Finghin, killed Dermod Maol MacCarthy (cousin of O'Donovan) who was engaged in a cattle-raid into O'Donovan's territory. Dermod Maol was regarded as the chief threat after Florence to the English in Munster (now along with O'Sullivan Beare, who joined the cause late) He and O'Sullivan Beare had been joined in continuing against the English by
Cornelius O'Driscoll, son of Sir Fineen who was now opposing them. After a period Finghin and Donogh Maol MacCarthy may have gone back to the rebel side but O'Donovan remained loyal to the English, even though his sept was divided in their allegiances. In July 1606, Donell M'Carthy, the M'Carthy Riough, petitioned the Earl of Salisbury that Donell O'Donevan, for whose loyalty petitioner's son was made surety and suffered four and a half years of imprisonment during the recent wars, should pay damages to him. Prior to the fall of the Gaelic order, it was common that pledges were secured by the holding of the offspring of those making the pledge, or in this case, those guarantying the conduct of those under them. ==Estate==