This painting refers to the courtly fantasy of British origins prevalent in the Elizabethan age and the seventeenth century. It illustrates Edmund Spenser's The Fairie Queene 1590/6, a poem that claims Elizabeth I as heir to King Arthur's British kingdom.
Arthegal was one of the Queene's knights, trained by the immortal Astraea to be the champion of True Justice. She gave him the invincible sword, Chrysaor, which he holds here. Behind him is Talus, his squire. Talus was a man 'made of iron mould, immoveable, resistlesse'. He carries an iron flail with which he threshes out falsehood.