Crown in 1585. The English authorities at Dublin Castle formed the new county by amalgamating the old Kingdom of Tír Chonaill with the old Lordship of Inishowen. However, although detachments of the Royal Irish Army were stationed there, the Dublin authorities were unable to establish control over Tír Chonaill and Inishowen until after the Battle of Kinsale in 1602. Full control over the new County Donegall was only achieved after the Flight of the Earls in September 1607. It was the centre of O'Doherty's Rebellion of 1608 with the key Battle of Kilmacrennan taking place there. The county was one of those 'planted' during the Plantation of Ulster from around 1610 onwards. What became the City of Derry was officially part of County Donegal up until 1610. County Donegal was one of the worst affected parts of Ulster during the Great Famine of the late 1840s in Ireland. Vast swathes of the county were devastated, with many areas becoming permanently depopulated. Vast numbers of County Donegal's people emigrated at this time, chiefly through Foyle Port. The Ballymanus mine disaster occurred on 10 May 1943 on a beach at Ballymanus, County Donegal, when local villagers attempted to bring ashore an unexploded marine mine. Eighteen men and boys between the ages of 13 and 34 were killed in the explosion. Effects of partition The partition of Ireland in the early 1920s had a massive direct impact on County Donegal. Partition cut the county off, economically and administratively, from Derry, which had acted for centuries as the county's main port, transport hub and financial centre. Derry, together with west Tyrone, was henceforward in a new, different jurisdiction which remained within the United Kingdom, a jurisdiction officially called Northern Ireland. Partition also meant that County Donegal was now almost entirely cut off from the rest of the jurisdiction in which it now found itself, the new dominion called the Irish Free State (later called Ireland from 1937). The county is physically connected to the rest of the Republic of Ireland by an internal border of only a few miles. The existence of a border cutting County Donegal off from her natural hinterlands in Derry City and West Tyrone greatly exacerbated the economic difficulties of the county after partition. The county's economy is particularly susceptible, just like that of Derry City, to the currency fluctuations of the euro against sterling. Added to all this, in