who was the convict at the three jolly bargement

The convict linked to the Three Jolly Bargemen in Great Expectations is usually understood to be Magwitch —more specifically, the mysterious stranger there is a released convict acting on Magwitch’s behalf, and later the connection to Magwitch becomes clear.

Quick read

• Pip and Joe encounter a strange man at the Three Jolly Bargemen.
• He turns out to be tied to the convict plot and later brings money to Pip.
• In the story, that thread points back to Magwitch.

Why the wording is confusing

The pub scene includes a convict-related stranger , not necessarily the same man Pip first met in the marshes. Dickens keeps the identity indirect at first, so readers often remember the pub as the place where the convict connection gets deeper.

Tiny spoiler note

If you meant the “mysterious stranger” at the pub , he is the one later associated with Magwitch and Pip’s secret benefactor storyline.

TL;DR: It’s Magwitch’s convict connection , and the man at the Three Jolly Bargemen is the important stranger tied to him.