The siege of Alexandria was a series of skirmishes and battles occurring between the forces of Julius Caesar, Cleopatra VII, Arsinoe IV, and Ptolemy XIII, between 48 and 47 BC. During this time Caesar was engaged in a civil war against remaining Republican forces. The siege was lifted by relief forces arriving from Syria. After a battle contesting those forces' crossing of the Nile delta, Ptolemy XIII and Arsinoe's forces were defeated.