From the Wikipedia: The Library of Celsus, the façade of which has been carefully reconstructed from all original pieces, it was originally built c. 125 AD in memory of Tiberius Julius Celsus Polemaeanus, an Ancient Greek who served as governor of Roman Asia (105–107) in the Roman Empire. Celsus paid for the construction of the library with his own personal wealth, and is buried in a sarcophagus beneath it. The library was mostly built by his son Gaius Julius Aquila and once held nearly 12,000 scrolls. Designed with an exaggerated entrance — so as to enhance its perceived size, speculate many historians — the building faces east so that the reading rooms could make best use of the morning light.

It was destroyed in 262. Celsus had been "proconsul" of the province of Asia, effectively governor of that province. He had done well, and the library was a monument, and actually his mausoleum. For his son managed to have him buried within the library (ordinary dead were never buried within the city walls), where his sarcophagus remained untouched until it was dug up in 1904.

Note: The statues adorning the façade of the Library of Celsus represent the Four Virtues or the Hellenic cultural values of Celsus: Sophia (Wisdom), Arete (Bravery), Episteme (Knowledge), and Ennoia (Thought). Originally, all these statues were made of bronze but they were, most possibly, melted down after the fire of the library in the 3rd century.

Sometime afterwards, they were replaced with female marble statues, evidently acquired from ruined buildings in Ephesus. Unfortunately, the statues that can be seen in Ephesus are just the modern-day copies as the originals are in the Ephesus Museum in Vienna.