In 633, when the Sasanian king Yazdegerd III was ruling over Iran, the Muslims under Umar invaded the country right after it had been in a bloody civil war.
Pada 633, sewaktu Yazdegerd III Raja Sasania memerintah atas Iran, kaum Muslim di bawah pimpinan Umar menginvasi negeri itu ketika pertumpahan darah akibat perang saudara baru saja usai.