Henri LaSalle the assigned Watcher for the Immortal Darius from 1774 to 1778.
In 1778 he married Babette Javert, acting as her recruiter and mentor in the Watcher organization.
The couple then worked together as a team for the next 21 years until Madame LaSalle's death in 1799. They were assigned to:
Andre Lagrace 1778 - 1782
Duncan MacLeod 1783 - 1784