BALTHASAR, servant to Romeo
ABRAM, servant to Montague
SAMPSON
& GREGORY
& CLOWN, servants to Capulet
PETER, servant to Juliet's Nurse
PAGE to Paris
APOTHECARY
Three MUSICIANS
LADY MONTAGUE, wife to Montague
LADY CAPULET, wife to Capulet
JULIET, daughter to Capulet
NURSE to Juliet
GENTLEMEN and GENTLEWOMEN, MASKERS, TORCH-BEARERS, OFFICERS of the Watch, other CITIZENS, SERVINGMEN and ATTENDANTS
SCENE: Verona, Mantua
The Nurse is Juliet’s  de facto  mother; as was usually the case with noble families, young children would be raised by a servant until they reached maturity. 
 The Nurse is a kindly character, aware of her own limitations, and who does her best to help Juliet find happiness with Romeo. He role in the play is large: she has lots of lines, especially early on, and is an important confidante for Juliet. 
 John Roddam Spencer Stanhope depiction: 

Romeo and Juliet Characters in the Play