Short answers, pulled from the story.
Vibia Sabina was a Roman empress who lived from 83 to 136 or 137 AD. She was the wife and second cousin once removed of the Emperor Hadrian, and the daughter of Matidia, who was a niece of Emperor Trajan.
Vibia Sabina was awarded the title of Augusta in 128 AD. It was the highest honorific available to an imperial woman in Rome.
Vibia Sabina was the first woman whose image appeared on a regular and continuous series of coins minted at Rome. No imperial woman before her had been depicted so consistently on official Roman coinage.
The almost complete statue, standing roughly 1.8 meters high and dating to the second century AD, was discovered by Theodore and Mabel Bent in March 1887. Ottoman authorities confiscated it before the Bents could take it to London, and it is now on display in the Archaeological Museum in Istanbul.
Vibia Sabina died before Hadrian, sometime in 136 or early 137 AD. Ancient sources differ on whether Hadrian treated her poorly or respected her, and some sources raise the possibility that she was driven to suicide.
The apotheosis relief depicts Sabina's divine ascent following her posthumous deification, which Hadrian ordered after her death. It was later incorporated as spolia into the Arch of Portugal and is now on display on the staircase of the Palazzo dei Conservatori at the Capitoline Museums in Rome.