The Codex Zacynthius, containing chapters 1:1-11:33 of the Gospel of Luke in Greek, was written in the sixth century, or possibly the seventh century, in an unknown location. The 176 leaf manuscript was palimpsested in the 12th of 13th century, and overwritten with weekday Gospel lessons. Its late Alexandrian text-type undertext, discovered as late as 1861, was written by two scribes in a single column in uncial script— a style very similar to that of the Rossano Gospels. The undertext is surrounded on three sides by a marginal commentary in a different, smaller uncial script; the codex is the oldest surviving manuscript incorporating this feature.
The early history of the codex is unknown. In its present sixteenth century Greek style goatskin binding it was presented to the British and Foreign Bible Society in 1821 by the General and abolitionist Colin Macaulay, as a gift from Prince Comuto of Zakynthos.
The undertext of the codex was discovered, deciphered, transcribed, and edited by English bible scholar and theologian Samuel Prideaux Tregelles, who published it in 1861 as Codex Zacynthius. Greek Palimpsest Fragments of the Gospel of Saint Luke, Obtained in the Island of Zante, by the Late General Colin Macaulay, and Now in the Library of the British and Foreign Bible Society. In his book Tregelles included one page of typographical facsimile showing the commentary in small type. He did not decipher the small Patristic writing, and doubted that it could be read without chemical restoration. For the main Greek text Tregelles used types originally cast for printing the Codex Alexandrinus, which only approximately represented the shape of the letters of the codex.
"The commentary is a catena of quotations of nine church fathers: Origen, Eusebius, Titus of Bostra, Basil, Isidore of Pelusium, Cyril of Alexandria, Sever from Antioch, Victor from Antioch, and Chrysostom. The commentary surrounds the single-column text of Luke on three sides. Patristic text is written in small uncial letters. Most of the quotations are those of Ciril of Alexandria (93 scholia); next comes Titus of Bostra (45 scholia). The commentary was written in a different kind of uncial script than the biblical text" (Wikipedia article on Codex Zacynthius, accessed 01-07-2014).
In 1984 the British Foreign and Bible Society, which owned the manuscript, placed the codex, and in 1985 their historical library on deposit with Cambridge University Library. On September 16, 2013 the society announced that it would sell the Codex Zacynthius as part of a fund raising campaign for a new visitor center in a deconsecrated church in North Wales. It offered Cambridge University the right of first refusal to purchase the manuscript at the price of £1.1m until February 2014. Cambridge University's press release, issued as part of its fund raising campaign, contained several fine images and useful commentary on the manuscript. In January 2014 it was available at this link. On April 6, 2014 the deadline for Cambridge to acquire the codex was extended to August 2014. On September 12, 2014 Cambridge announced that its fundraising campaign to acquire the manuscript had been a success.