Ephesus was one of the great cities of Roman Asia, a harbour town of perhaps two hundred thousand people, with the Temple of Artemis outside the walls and a theatre cut into the hillside holding twenty five thousand. The Library of Celsus stands at the heart of it, where Curetes Street meets the Marble Road beside the commercial agora. It was built as two things at once, a public library and a tomb. Tiberius Julius Aquila raised it for his father, Tiberius Julius Celsus Polemaeanus, a Roman senator who had been consul in 92 and proconsul of Asia around 105 to 107. Burial inside a city was not normally permitted. Celsus was granted it, and his marble sarcophagus still lies in a sealed crypt beneath the floor of the reading hall, rediscovered in 1904 and never opened.

Building began around 110 and the library was finished somewhere between 117 and 135. Aquila died before it was done and his heirs saw it through. Niches in the reading hall walls held papyrus rolls, the figure usually given as twelve thousand, with a possible capacity closer to sixteen thousand if free standing book boxes stood in the room as well. Nothing could be borrowed. Copies were far too costly to let out of the building.

No catalogue survives of which particular works sat in those niches. Guides sometimes quote Heraclitus or Saint Paul to have visited, but Heraclitus died six centuries earlier, and Paul was preaching in Ephesus in the fifties, around sixty years before the first stone was laid. What can be said is that it served a city already known for learning and for early Christian scholarship, and that it stood open to the public rather than to one household.

The end came in 262. The interior burned and the scrolls went with it, in a year when Ephesus suffered both a severe December earthquake and a Gothic raid. The reading hall was never rebuilt. The facade survived and kept standing, the forecourt turned into a pool in the fourth century, until an earthquake in the tenth or eleventh century brought it down. It lay buried until Austrian archaeologists identified it in 1903. What is seen today was re-erected between 1970 and 1978 by anastylosis, using the original fallen stones wherever they could be matched and replicas for the rest. The four figures in the niches, Sophia, Arete, Ennoia and Episteme, are copies. The originals went to Vienna in 1910.