in Leinster in the 1550s, when the O'Moore and O'Connor clans were displaced to make way for the Plantation of Queen's County and King's County (named for Mary I of England and Philip II of Spain; modern counties Laois and Offaly). In the 1560s, English attempts to interfere in a succession dispute within the O'Neill sept, or clan, sparked a long war between Thomas Radcliffe (Lord Deputy of Sussex) and Seán Mac Cuinn Ó Néill. Irish lordships continued to fight private wars against each other, ignoring the government in Dublin and its laws. Two examples of this were the Battle of Affane in 1565, fought between the Ormonde and Desmond dynasties, and the Battle of Farsetmore in 1567, fought between the O'Donnells and O'Neills. Elsewhere, clans such as the O'Byrnes and O'Tooles continued raiding the Pale as they had always done. The most serious violence of all occurred in Munster in the 1560s to 1580s, when the Fitzgeralds of Desmond launched the Desmond Rebellions to prevent direct English influence into their territory. After a particularly brutal campaign in which up to a third of the population of the province was reported to have died, the rebellion was finally ended when the Earl of Desmond was killed in 1583. There were two main reasons for the chronic violence that dogged the central government in Ireland. The first was some of the aggressive acts of the English administrators and soldiers. In many instances, garrisons or "seneschals" disregarded the law and killed local chiefs and lords, and sometimes seized native-owned land. The second cause of violence was the incompatibility of Gaelic Irish society with English law and central government. In Irish law, the chief of a sept or clan was elected from a small noble lineage group called a . This often caused violence between rival candidates. However, under Henry VIII's settlement, succession was, as was the English custom, by inheritance of the first-born son, or primogeniture, which was intended to result in fewer disputes over inheritance but also in an increasing reduction in the distribution of landed wealth. Imposing this law forced the English to take sides in violent disputes within Irish lordships. Finally, important sections of Irish society had a vested interest in opposing the English presence. These included the mercenary class or gallowglass, and Irish poets or – both of whom faced having their source of income and status abolished