Watchers of the Lake

The Watchers of the Lake, also known as the Lake Watchers, Watchers of Esgaroth, or simply known as the Watchers, are the townsguard that are tasked with upholding law and order upon the Esgaroth, located at the very heart of the Long Lake within Rhovanion.

Quest for Erebor
During the Quest for Erebor in TA 2941, many of the watchers started to question their loyalty towards the Master of Esgaroth, in which some had been planning to forge a mutiny against him, something that would soon start the riots in Esgaroth and remove the Master out of power. That was when Thorin Oakenshield and his company traveled to Esgaroth where they tried to steal weapons and a boat to sail to the shore which would take them directly to the Lonely Mountain, however, that was when they were caught by a group of watchers that found them stealing and brought them to the Master of Esgaroth. Once Thorin and his dwarves reveal themselves, many of the Watchers were willing to get a fair share of the treasure and would continue their job as watchers as long as they get paid for their job they've done over the years.

After Thorin had promised the people of Esgaroth an honorable share of the gold in Erebor as long as they were allowed to proceed with their mission to put an end to Smaug's reign of terror once and for all. When the Dwarves entered the Mountain, Smaug attacked and set Esgaroth ablaze - destroying every home in Esgaroth. The Watchers of the Lake were furious of the Master's abandoning the people and chose to follow Bard as their ruler and king. Taking refuge in the ruined city of Dale, the Watchers of the Lake did their job by taking the night watch and keeping their eyes open for any enemy activity. That was when by morning, they would witness the arrival of King Thranduil leading an army of elves to the mountain and provisions to give to the people of Esgaroth.

Despite Thorin's refusal in giving them their payment, the Watchers of the Lake were part of Bard's grand army and aided with the Elves to fight against the Dwarves.

Military
There were over 60,000 Watchers that guarded every corner of Esgaroth. Hundreds were killed in its destruction while thousands were badly injured in the attack and taken to Dale to recover from their injuries. More than 50,000 Watchers of the Lake remained uninjured and joined Bard's army. After the rebuilding of Dale and Esgaroth, the Watchers of the Lake continued to do their job and bring in new recruits. At the time of the War of the Ring, more than 75,000 Watchers of the Lake were involved in the Battle of Rhovanion and fought bravely to protect Esgaroth.