The New Churchyard was the first of the early modern non-parochial City burial grounds. It was established on land that had been part of the priory of St Mary Bethlehem and so became known as the Bethlehem Churchyard or the Old Bethlehem Burying Ground. This was often abbreviated to Bethlem or Bedlam. The churchyard remained in use for 170 years and closed in 1739.
The Crossrail excavations lay within the south-western part of the burial ground and over 3,300 burials were uncovered. Among these was a mass grave containing 42 individuals, but which may have originally held more than 100. It is thought to have been dug during one of the plague outbreaks in the late 16th or early 17th century.
The Great Plague of 1665 is the most famous outbreak. It killed about 100,000 people in London, almost a quarter of the population.
Five of the individuals have tested positive for the plague pathogen. This is the first ever identification of plague DNA from 16th-17th century Britain.