The National Archives (the official archive of the UK government) describes it as "a compilation of charters, statutes and customs".
[1] It is thought to have been a compilation of two separate books: De Veteribus Legibus Angliae and De Statutes.
The Oxford Dictionary of National Biography describes it as "the most comprehensive of all statute collections".
[2][3] Portions of Liber Horn were reproduced in Statutes of the Realm, Volume 1.
This article about a book on politics of England is a stub.