Master of Lake-town

The Master of Lake-Town or The Master was the original leader of Laketown when Bilbo Baggins and his companions arrived. He is described as being greedy, but not undeserving of his position in terms of intelligence and charisma. Contrary to popular opinion, he was not a rival or enemy of Bard the Bowman, but rather a close companion of Bard's, and he even allowed Bard to remain in Esgaroth while the Lakemen recovered from their ordeal with Smaug.

In The Hobbit he is not given an actual name.

History
The Master of Laketown ruled from 2920 of the Third Age of Sun to 2941 of the Third Age of Sun, and he would have been approximately thirty years old when he began leadership. This would make him fifty years old at the time of the Battle of the Five Armies and The Quest of Erebor, as these events both occurred in the year 2941. The Master's rule in Laketown was rather amicable, and therefore under his dominion the Men of the Long Lake traded peaceably with the Elves of Mirkwood, creating a steady trade that was kept until 2941, when Thorin and his friends came to wrest dominion of the Lonely Mountain (Erebor) and its riches from Smaug, who had arrived 120 years before the Master's rule, in the year 2770.

When the dwarves arrived, the Master of Laketown greeted them generously, but only to keep public spirits up. After the destruction of Esgaroth and the slaying of the dragon by Bard, he was given money for the rebuilding of Laketown by Dain II Ironfoot, the ruler of the Lonely Mountain. He is therefore described as weak, because he is easily overcome by the lust of the treasure Smaug held, and by the dragon-spell. He flees into the wild with the gold, and is eventually abandoned in the waste and perishes there of starvation.

Rankin/Bass's The Hobbit
The Master is not shown.

Peter Jackson's The Hobbit film series
In the Peter Jackson adaptation of The Hobbit, set to release in December 2012, The Master is played by the English actor Stephen Fry.

Play
In the play adaptation of The Hobbit by Edward Mast, The Master of Laketown is named Maxwell, though this is not considered canon.