Emperor Justinian I commissions in 532, after the destruction of the earlier basilica during the Nika revolt, the construction of a new cathedral in Constantinople from two mathematicians and geometers: Anthemius of Tralles and Isidore of Miletus. To support a dome of unprecedented dimensions on a square base, they develop at large scale the pendentive technique: curved triangular sections that transfer the dome's circular weight to four massive piers at the corners of the square plan, without needing columns to interrupt the interior space. Construction is completed in 537, after only five years of work with up to ten thousand workers. The original dome partially collapsed in an earthquake in 558 and was rebuilt by Isidore the Younger, nephew of Isidore of Miletus, with structural improvements. Hagia Sophia became the architectural reference model for eastern Christendom for a millennium.