Why is londonderry called londonderry?

Derry or Londonderry is a city and district in Northern Ireland, United Kingdom. Derry is the traditional name used by natives of the city and the surrounding area. The name Londonderry is the official title of the city, and is used by some Unionist politicians and organisations, as well as by the British government. The name Derry is derived from the Irish word Doire, meaning "oak grove". The name Londonderry was officially granted to the city in 1613, when King James I of England and VI of Scotland issued a charter to the city. The charter declared that the city would be known as "the city of Londonderry", and that its citizens would be known as "the citizens of the city of Londonderry". The name Londonderry was chosen in honour of the City of London, which had funded the plantation of Ulster. The name Derry has been used as an alternative to Londonderry since the 17th century. The name Londonderry has been associated with the city's Protestant population, while the name Derry has been associated with the city's Catholic population. The use of the name Derry or Londonderry has been a source of controversy in Northern Ireland.