The Library of Celsus (Greek: Βιβλιοθήκη του Κέλσου) is an ancient Roman building in Ephesus, Anatolia, today located near the modern town of Selçuk, in the İzmir Province of western Turkey.

After Celsus' death, his son Tiberius Julius Aquila Polemaeanus commissioned the library in his father's honor, using Greek and Roman techniques.

[4] In Ancient Roman culture, the wealthy and privileged were expected to act as benefactors, and use their wealth for the greater good of the community.

[18] Design features include acanthus leaves, scrolls, and fasces emblems, the latter being a symbol of magisterial power that alludes to Celsus's tenure as a consul.

The columns on the lower level frame four aediculae containing statues of female personifications of virtues: Sophia (wisdom), Episteme (knowledge), Ennoia (intelligence), and Arete (excellence).

This type of façade with inset frames and niches for statues is similar to that of the skene found in ancient Greek theatres and is thus characterized as "scenographic".

[13] Several Roman motifs appeared throughout the library, including reliefs fashioned after Julius Caesar's that had never been seen before in Ephesus or Asia Minor in general.

The interior of the building, which has yet to be restored, consisted of a single rectangular room measuring 17x11 m, with a central apse framed by a large arch at the far wall.

The apse contained a podium for a statue, now lost, that likely depicted Celsus, although some scholars have suggested it was Minerva, Roman goddess of wisdom.

[24][19] It was unusual in Roman culture for someone to be buried within a library or even within city limits, so this was a special honour for Celsus, reflecting his prominent role as a public official.

[28] The design of the library, with its ornate, balanced façade, reflects the influence of Greek style on Roman architecture, which reached its height in the second century.

[3] He is depicted with a strong jaw, curly hair, and a neat beard, Hellenizing portrait features that echo the stylistic choices of the building's façade.

[3] The style imitates traits of Hadrianic imperial portraiture, suggesting that it was sculpted after the lifetime of not only Celsus, but of his son Aquila as well.

The choice to depict him in full armor suggests that Celsus's descendants considered his military career memorable and a source of pride.