Where the name 'Shadwell' comes from is unclear: a shallow creek or St Chad's well.
In the 13th century the low-lying marsh here was called Scadflet or Shatfliet, from Anglo-Saxon fleot, a shallow creek or bay. A spring near the churchyard, dedicated to St Chad, filled a nearby well, and the place was once called Chadwelle, though this may be a false etymology. A mill called Sathewell or Shadwell existed before 1198.