The Edge of the World: How the North Sea Made Us Who We Are by Michael Pye

that we owe them literacy and not just in Latin. But the story is more
     complicated than that. The habit of writing and reading had reached Ireland before St
     Patrick came over on his mission; and what brought it was the trade that went back and
     forth across the sea.
    For Ireland wasn’t isolated before the
     missionaries arrived. Tacitus says the approaches to its ports were well known to
     traders in the first century CE . Words crossed from Latin into Irish even
     if Irish made them hard to pronounce; so the Latin
purpura
for fine cloth
     turned into
corcur
; the Irish
long
, a ship, is from the Latin for a
     longship,
navis longa
; and the Irish
ingor
comes from the Latin
ancora
, for an anchor. These are sea words, about sailing and about the
     goods that ships were carrying, and the words made the crossing before thefifth century. Military words also crossed,
     words the Christian missionaries did not need: words for a legion, a soldier, weapons
     and weekday names that are tributes to Roman gods such as
Mercúir
for Wednesday
     (and Mercury) and
Saturn
for Saturday.
    The Irish were outside the empire, so they
     did not have to play by Roman rules. They did not need reading and writing in order to
     rise in the imperial bureaucracy. They settled questions about who owned which piece of
     land by hearing witnesses and swearing oaths and paying attention to the memory of a
     community. When they first carved words onto stone, using the Irish
ogam
script, they were making simple memorials to the names of the dead, markers that were
     solid enough to stand as boundary markers and more reliable than memory. But the Irish
     were also trading with the Romans, and that required either memory or records that the
     Romans would understand; in their voyages to Gaul or to Wales, the Irish quickly learned
     that the Romans’ language was different, and was written a different way. At the
     same time they were working out their own way of writing down their Irish language. The
ogam
alphabet grew out of the marks made on wooden tally sticks to count
     sheep and cattle, but its other purpose may have been to mystify the Roman functionaries
     and merchants, who knew only their own letters.
    This meant that when Patrick arrived to
     convert Ireland in the fifth century, he had a head start. He was preaching the faith of
     the Book, carrying with him books of the law and the Gospels, and the Irish had their
     own habit of writing and reading already. They knew something about the technology.
     There are clues in the Irish law tracts written later, in the seventh century, which lay
     down that a contract can be proved by, among other things, ‘a godly old
     writing’, and witnesses can make a dead man’s agreement stand but only if
     they are not contradicted by relevant texts cut onto stones. Writing settles deep into
     Irish law. 37 Much more remarkably, in his life of Patrick, the seventh-century monk
     Muirchú tells how the missionary found himself in a contest of magic with King
     Lóeguire’s druid. The king told the two to pitch their books into the water, and
     they’d see which god was worth adoring. The druid said he’d rather not
     because he knew about baptism and Patrick’s God was obviously a water god.
     It’s true that Muirchú was writing two hundred years later, and maybe he took for
     granted that the Irish had always had books because he had them himself, but the more
     likely story is literal: druids had some form of book, perhaps metal leaves, perhaps
     wood or stone, which could rival the Book. Patrick taught some men their alphabet to
     make them priests and bishops, but not all men needed the lessons. 38
    This fact that the Irish wrote down Irish
     very early still matters very much: it made books useful.
    Books could always be lovely things, used
     like jewels: sealed into shrines or put on an altar where nobody could possibly read
     them or sent to Rome as splendid presents for the Pope.
    Boniface