Question: Londonderry Borough Police are the force in the county that is part of what country?

Context paragraphs:
Reading Borough Police: Reading Borough Police was a police force for the borough of Reading in the United Kingdom.  The force was created on 21 February 1836, at which time it had a strength of 30 constables, two sergeants and two inspectors. Towards the end of the 19th century, Reading Borough Police had increased in size to 62 officers.  However, the local population had risen to around 60,500, which meant one officer for every 1,000 inhabitants.  By the time of the First World War the force had an establishment of 113 officers, however, due to military service only 30 officers were patrolling Reading.

Londonderry County Borough Council election, 1920: An election to Londonderry County Borough Council took place in January 1920 as part of that year's Irish local elections.  The Local Government (Ireland) Act 1919 had seen elections for local government in Ireland change to a more proportional system.  As a result Unionists lost control over Londonderry borough council, which for the first time passed into the control of the city's Catholic majority.

St Ives Borough Police: St Ives Borough Police was the borough police force for the town of St Ives, Cornwall, from 1836 to 1889.  It was established following the passage of the Municipal Corporations Act 1835.  The force was unique in that it only boasted a single constable at any one time throughout its entire existence.

County Londonderry: Since 1972, the counties in Northern Ireland; including Londonderry; have no longer been used by the state as part of the local administration.  Following further reforms in 2015, the area is now governed under three different districts; Derry and Strabane, Causeway Coast and Glens and Mid-Ulster.  Despite no longer being used for local government and administrative purposes, it is sometimes used in a cultural context in All-Ireland sporting and cultural events (ie - Derry GAA).

Penzance Borough Police: Penzance Borough Police was the police force for the borough and corporate town of Penzance, Cornwall, from 1836 to 1947.  It was formed following the passing of the Municipal Corporations Act 1835, which reformed all UK boroughs, and stipulated that each appoint a Watch Committee to oversee a police force.  The police force formed part of the commonality of the town’s government, led by an elected Mayor, six aldermen and eighteen councillors.

Law enforcement in Ireland: This is a description of law enforcement in Northern Ireland and the Republic of Ireland.  Before the Republic (then called the Irish Free State) left the union, one police force - the Royal Irish Constabulary - policed almost the whole island (aside from Dublin, where the Dublin Metropolitan Police were the main force, Belfast where the Belfast Borough Police were the main force and the borough of Londonderry where the Londonderry Borough Police were the main force before merging with the RIC.  See List of defunct law enforcement agencies in the United Kingdom and Irish Police records and also Royal Irish Constabulary Forum for other forces in Ireland that have been disbanded.) .

Newcastle upon Tyne City Police: Newcastle upon Tyne City Police also known as Newcastle upon Tyne Borough Police, was the Home office Police force and a Constabulary that served the City of Newcastle upon Tyne with origins in 1836.  On 1 April 1969 it was amalgamated into the Northumberland Constabulary under the Police Act 1964.  The first Modern Police Force was formed in Newcastle in 1836, 3 years before the County Police Act of 1839.

Londonderry Borough Police: The Londonderry Borough Police was the police force in the city of Derry, County Londonderry, Ireland from 1848 to 1870, nicknamed the Horney Dicks after the bones used in their helmets.  They replaced the earlier town watch and were in turn replaced by the Royal Irish Constabulary.  The police force was established by the Londonderry Improvement Act 1848 and were governed by the Londonderry Corporation.  Its abolition was recommended by a commission of inquiry into sectarian riots in the city in 1869.  The commission felt the force, having the form of a town watch, was inadequate to policing serious crime; it also noted, but did not endorse, allegations that the police discriminated against Roman Catholics.

Folkestone Borough Police: Folkestone Borough Police was the borough police force for the town of Folkestone in Kent.  It was formed in 1851 under the terms of the Municipal Corporations Act 1835.

Ferguson baronets: The Ferguson Baronetcy, of the City of Londonderry, was a title in the Baronetage of the United Kingdom.  It was created on 7 October 1801 for Andrew Ferguson, who had previously represented Londonderry Borough in the Irish House of Commons.  The second Baronet represented Londonderry in the British House of Commons.  The title became extinct on his death in 1860.

Supporting paragraphs: Londonderry Borough Police County Londonderry
Answer: Northern Ireland