1
general::
Phrase(s): bring up the rear
to move along behind everyone else; to be at the end of the line. (Originally referred to marching soldiers. Fixed order.) • Here comes John, bringing up the rear. • Hurry up, Tom! Why are you always bringing up the rear?
McGrawhill's American Idioms And Phrasal Verbs
2
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Be last in a line or sequence, as in As a slow walker, I'm used to bringing up the rear, or In test results Tom always brought up the rear. This term almost certainly came from the military but the earliest citation given by the Oxford English Dictionary is from a 1643 religious treatise by Sir Thomas Browne: "My desires onely are . . . to be but the last man, and bring up the Rere in Heaven."
American Heritage Idioms