Final answer:
Henry Purcell was employed at the court of King Charles II when he wrote 'Dido and Aeneas'.
Step-by-step explanation:
Henry Purcell was employed at the court of the English monarch, King Charles II, when he wrote the opera 'Dido and Aeneas'. Purcell was appointed as a court musician and composer, and he composed numerous works for important royal events and theatrical productions. 'Dido and Aeneas' is one of Purcell's most famous works and remains a significant contribution to English Baroque opera.