The diaries of a 19th Century Yorkshire woman who flouted convention have been recognised by the United Nations as a "pivotal" document in British history.
Anne Lister's diaries tell the story of her life and her lesbian relationships at Shibden Hall in Halifax.
Her diaries are one of just 20 unique items to be added to the UK Memory of the World register in 2011.
The register, compiled by UN cultural organisation Unesco, is an online archive of historic UK documents.
Anne Lister lived at Shibden Hall between 1791 and 1840 and her journals, which amount to over four million words, give an insight into her life as a lover, traveller and landowner.
A Unesco committee voted to add the diaries to the Memory of the World register, describing them as "a comprehensive and painfully honest account of lesbian life and reflections on her nature".
Helena Whitbread, Anne Lister's biographer, said she was delighted the importance of the diaries had been recognised.
"The award seals the rightful place of the Anne Lister journals and correspondence in the register of archive treasures," she said.
"They are a national treasure of international renown."
The diaries, which were the subject of a BBC television drama in 2010, are stored at the West Yorkshire archives in Halifax.
Other additions to the UK Memory of the World register in 2011 include documents from the Nazi occupation of Jersey in World War II and the death warrant of King Charles I.