André Rooryck was born in Izenberge, Belgium to a brewer on July 17, 1923. He attended the University of Louvain in the late 1940s, studying philosophy and theology before taking a BA in Classical Philology and a Law Doctorate.

Starting work in the documentation centre of the Algemeen Christelijk Vakverbond, the Belgian Catholic trade union, he was asked in 1957, to join Caritas Catholica, a confederation of Catholic relief, development and social service organisations.

He eventually became a director at the Verbond voor Verpleeginstellingen - an association representing the Catholic hospitals and retirement homes, which were still largely run charitably by religious orders at the time.

Rooryck took early retirement in 1986, at which time he was awarded the Holy Cross Pro Ecclesia et Pontifice, an award given for distinguished service to the church. A devout Catholic, Rooryck considered this to be the highlight of his career.

His retirement allowed him to pursue full time his passion for studying and collecting books, which was also driven in part by his religious and philosophical interests. He had begun collecting medieval manuscripts in the 1970s and became fascinated in them both as texts and as objects.

Johannes Charlier (Jean) de Gerson's work De Simonia (Click to enlarge)

Some of his most cherished works included On Simony by theologian Jean Gerson, who addressed the Council of Constance (which re-united the Papacy), and Cases of Conscience by the Franciscan canon lawyer and theologian Astesanus de Ast.

He also owned a first edition of Leonardus Matthaei de Utino's Sermones Quadragesimales de Legibus, a copy of which, from the Estelle Doheny collection, outstripped its $3,000-4,000 estimate at Christie's in 2001 to sell for $9,988.

Rooryck also had an interest in ancient history, and owned one of the earliest printed versions of Suetonius's classic history of the first 12 Roman Emperors, published in 1475.

Suetonius's History of the first 12 Emperors (Click to enlarge)

An expert in palaeography (the understanding of very old texts for deciphering and dating purposes) Rooryck transcribed and annotated every text in his collection in his spidery handwriting, pestering librarians around the world to send him copies of pages damaged or illegible in his own copies.

These, and many other early books and incunabula (early printing - anything done in 1500 or earlier) are soon to be sold at Bloomsbury Auctions.

In the early 1990s, Rooryck found that his interest in history could also be satisfied by coins, and a fresh collection of coins from the Ancient world began.

Early coin from the ancient city of Himera in Sicily

In total, he brought together 187 coins from Antiquity, including Greek, Roman, and Celtic coins, ranging from Asia Minor to Spain, and from the sixth century BC to the second century AD. These too were the subject of meticulous study and annotation, and will be the subject of a major sale at Jean Elsen et ses Fils in a few weeks' time.

Rooryck passed away in his home in Nossegem (Zaventem) in spring, 2010, but his name is likely to live on for a long time. Rare and collectible books sometimes carry 'ex-Rooryck' as part of their description, and he is credited with preserving and deciphering copies of works which are now in libraries around the world.

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