Donal Cam O'Sullivan Beare

Donal Cam O'Sullivan Beare, Prince of Beare, 1st Count of Berehaven (Irish: Domhnall Cam Ó Súilleabháin Bhéara) (1561–1618) was the last independent ruler of the O'Sullivan Beara sept, and thus the last O'Sullivan Beare, a Gaelic princely title, in the southwest of Ireland during the early seventeenth century, when the English crown was attempting to secure their rule over the whole island.

Donal's father was killed in 1563, but he was considered too young to inherit and the clan leadership passed to the chief's surviving brother Eoin, who was confirmed by English authorities in Dublin with the title Lord of Beare and Bantry. To consolidate his position, Eoin accepted the authority of Queen Elizabeth I of England and was knighted. In 1587 Donal asserted his own claim to leadership of the clan, petitioning Dublin to put aside Eoin's appointment with a claim derived from English laws based on absolute male primogeniture. These laws did not recognise age as relevant to inheritance rights. Keen to extend English legal authority over Ireland, the Dublin commission accepted Donal's claim. He now became The O'Sullivan Beare, head of the clan.

By 1600 Munster had been devastated by battle, and the Gaelic clans lost over half a million acres (4,000 km²) of land to settlers from England following the defeat of the Desmond Rebellions.

In the lead up to the Nine Years' War O'Sullivan kept his distance from the rebel cause, but in time he joined a confederation of Gaelic chiefs led by Hugh O'Neill, Earl of Tyrone and Hugh Roe O'Donnell of Ulster. Conflict had broken out in 1594, and O'Neill secured support from Philip II of Spain. The Spanish sent a force under the command of Don Juan D'Aquilla in 1601. O'Sullivan wrote to the Spanish king in submission to his authority, but the letter was intercepted by the English. In early 1602 the allied Irish and Spanish forces met the English at the Battle of Kinsale and were defeated.

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