Sometimes books are marked by their former owners. In some cases with (armorial) bookplates, in other cases with just a handwritten name. Instead of an ownership marking they also may contain a gift inscription from the author. Important provenance usually will increase the value of a book. Here below some examples.
BOOKPLATES
Mainly in the past bibliophiles marked their books with an ‘ex libris’, a bookplate that contained their name, often with a small picture showing who they were or what they did. Ususally it was glued on the front pastedown. Here below some examples with their name and the title of the book in which they are found. All books without exception are first editions.

The armorial bookplate of Maximilian Joseph Eugene Auguste Napoleon de Beauharnais, 3rd Duke of Leuchtenberg, Prince Romanowsky. He was a son in law of Tsar Nicholas the first of Russia and a cousin both of emperor Napoleon III of France and of Franz Joseph I, emperor of Austria and king of Hungary. (Book: Paris 1851; Voyage en Perse. by Alexis Soltykoff.)

The armorial bookplate of the first Duke of Sussex, a son of King George III. (Book: A True Historicall discourse of Muley Hamets rising to the three Kingdomes of Moruecos, Fes and Sus. The dis-vnion of the three Kingdomes by ciuill warre, kindled amongst his three ambitious Sonnes, Muley Sheck, Muley Boferes and Muley Sidan. The Religion and Policie of the More, or Barbarian. The aduentures of Sir Anthony Sherley, and diuers other English Gentlemen, in those Countries. With other Nouelties. London 1609; by Robert Coverte [?])

A peculiar armorial bookplate of Marquis de Bassano. Hugues-Bernard Maret was knighted in 1809, at first he got the title of count and only two months later he was promoted Duke of Bassano. A marquess, however, seems to be untraceable. (Book: The Voyages, Dangerous Adventures And imminent Escapes of Captain Richard Falconer: containing the Laws, Customs, and Manners of the Indians in America; his Shipwrecks; his Marrying an Indian Wife; his narrow Escape from the Island of Dominico, &c. Intermix’d with The Voyages and Adventures of THOMAS RANDAL, of Cork, pilot; with his Shipwreck in the Baltick, being the only Man that escap’d: His being taken by the Indians of Virginia, &c: Written by Himself, now alive. London 1720; published anonymously, but is attributed to William Rufus Chetwood.)

The armorial bookplate of Charles Robert Scott-Murray of Danesfield, who has been a Member of Parliament for Buckinghamshire and later became High Sheriff of that county. (Book: Travels Through Central Africa to Timbuctoo; and Across the Great Desert, to Morocco, Performed in the Years 1824-1828. London 1830; by René Caillié.)

The armorial bookplate of William Thomas Rowland Powell (1815 – 1878) of Nanteos Mansion, Cardiganshire, with his motto “Inter hastas et hostes”. (Book: De Expedit. Alex. Magni, Historiarum Libri VIII, (bound with:) Arriani historici et philosophi Ponti Euxini & maris Erythraei Periplus, ad Adrianum Caesarem. Geneva 1575; by Flavius Arrianus.)

Bookplate of Francis White related to profession; Francis White was an American diplomat, stationed in many cities. (Book: History of Nepal, translated from the Parbatiya by Munshi Shew Shunker Singh and Pandit Shri Gunanand: with an introductory sketch of the country and people of Nepal. Cambridge 1877; edited by Daniel Wright.)

Bookplate of G.R. Nicolaus, bibliophile and a big game hunter related to hobby. (Book: Sketches representing the Native Tribes, Animals, and Scenery of Southern Africa, from Drawings made by the late Mr. Samuel Daniell, engraved by William Daniell. London 1820.)

A bookplate that is often mistakenly considered the be the bookplate of Pierre Guiraud, but it is a more complicated bookplate. It was lithographed by Durand and is exceptional in the way that it combines the coat of arms of the counts of Balincourt with the names of the people that, by inheritance, contributed to the collection of Edgard Testu comte de Balincourt. The basis for the collection was laid by Pierre Guiraud (born in 1656) who bequeathed it to Jean Maurice Reinaud (1706 – 1792). The next owner was Jean Jacques Maurice Reinaud de Gênas who left his collection to Edgard Testu de Balincourt (1832 – 1914). The latter was the one who designed this bookplate with at the upper side the original bookplate of Pierre Guiraud with his motto “Da laborem dabo fructus” combined with parts of the bookplates of the other two previous owners and at the lower side the coat of arms of the counts of Balincourt. At the top it reads “1680 – 1880”. The first year refers to the marriage of Marguerite Guiraud, sister of Pierre Guiraud, with Jean Maurice Fauquier while in 1880 this bookplate was designed by Edgard Testu. (Book: Traitté qui contient la methode la plus facile et la plus asseurée pour convertir ceux qui se sont separez de l’Eglise. Paris 1651; by Cardinal de Richelieu.)
INSCRIPTIONS

The ownership inscription of René Basset, the French orientalist and linguist, especially known for his work on the Arabic and Berber languages, in Godefroy Loyer’s “Relation du voyage du Royaume d’Issyny”, published in 1714 by Arnoul Seneuze et Jean-Raoul Morel.

Ricardo Caminos’ ownership inscription in the first edition of “Notes on the story of Sinuhe” by Alan H. Gardiner, published in 1916 by Librairie Honoré Champion. Ricardo Caminos was an Argentine Egyptologist renowned for his expertise in hieroglyphic epigraphy and paleography.

A gift inscription by Hugues Krafft in his book “A travers le Turkestan Russe” for Alfred Grandidier who, at the time, was the president of the Société de Géographie, while Krafft was an important member of that organisation. Krafft’s book was published in 1902 by Hachette.

A gift inscription by Borelli in his book “Éthiopie Méridionale. Journal de mon Voyage aux Pays Amhara, Oromo et Sidama” for Marquess Menabrea. The book was published by Ancienne Maison Quentin in 1890.
General Luigi Frederico Menabrea, Marquess of Valdora, was born at Chambry on September 4th, 1809. He was educated at the university of Turin, where he qualified as an engineer and became a doctor of mathematics. He joined the army, where he reached the rank of general. In 1848 he was sent by King Charles Albert on diplomatic missions to secure the adhesion of Modena and Parma to Sardinia. He entered the Ricasoli cabinet of 1861 as minister of marine and held the portfolio of public works until 1864 in the succeeding Farini and Minghetti cabinets. After the war of 1866 between Italy and Austria he was chosen as Italian plenipotentiary for the negotiation of the treaty of Prague and for the transfer of Venice to Italy. In October 1867 he succeeded Rattazzi in the premiership. After a series of changes in the cabinet, and many crises, Menabrea resigned in December 1869 on the election of a new chamber in which he did not command a majority. His successor in the premiership, Giovanni Lanza, in order to remove him from his influential position as aide-de-camp to the king, sent him to London as ambassador, where he remained until, in 1882, he succeeded General Cialdini as embassador in Paris. Ten years later he withdrew from public life, and died at Saint Capin on the 24th of May 1896.
Despite all the above mentioned important achievements, internationally he is best remembered as a gifted mathematician who in 1842 published his “Sketch of The Analytical Engine invented by Charles Babbage” (With notes upon the Memoir by the Translator, Ada Augusta, Countess of Lovelace; Bibliotheque Universelle de Geneve, October 1842, no. 82).