(1800–1886), who, on inheriting the estate in 1840, adopted the hyphenated surname of Douglas-Pennant. Edward, the grandson of the 14th Earl of Morton, was created the 1st Baron Penrhyn (second creation) in the Peerage of the United Kingdom in 1866. In accordance with his father-in-law’s wishes, he assembled a major collection of pictures for the castle. He was succeeded by his son, George Douglas-Pennant, 2nd Baron Penrhyn, in 1886. He was, in turn, succeeded by his son, Edward Douglas-Pennant, 3rd Baron Penrhyn, who lost his eldest son, and two half-brothers, as casualties in World War I. Hugh Douglas-Pennant, 4th Baron Penrhyn, who inherited the title and estates in 1927, died in June 1949, when the castle and estate passed to his niece, Lady Janet Pelham, who, following family tradition, adopted the surname of Douglas-Pennant. In 1951, the castle and 40,000 acres (160 km2) of land were accepted by the treasury in lieu of death duties and ownership was transferred to the National Trust. 21st century The National Trust has held custodianship of Penrhyn Castle since its transfer by the government in 1951. It has worked to conserve the house and its setting, and develop its attraction to visitors. In 2019/2020 Penrhyn received 139,614 such visitors, an increase over the two previous years (118,833 and 109,395). In the 21st century, the Trust has sought to develop its understanding and coverage of the links between the house and colonialism and slavery (see below). The Trust's 2022 Penrhyn Castle website records: "we are accelerating plans to reinterpret the stories of the painful and challenging histories attached to Penrhyn Castle. This will take time as we want to ensure that changes we make are sustained and underpinned by high quality research." A large collection of Douglas-Pennant family papers is held by Bangor University and was catalogued between 2015-2017. Slavery and slate Slavery For much of the 20th century, conservation bodies such as the Trust largely ignored the issues of slavery and colonialism in relation to their properties. This position began to change at the very end of the century. In 1995, Alaistair Hennesey published a pioneering article on Penrhyn and slavery in History Today. Of Penrhyn, Hennesey wrote, “there is no building which illustrates so graphically the role which slave plantation profits played in the growth of British economic power." In 2009 the Trust organised a symposium, Slavery and the British Country House, in