Wicket Wystri Warrick is an Ewok scout of Bright Tree Village on the forest moon of Endor, and the first of his people the audience meets in Return of the Jedi (1983). Warwick Davis, then eleven years old, performs him.
The scene that sells the species
He finds an unconscious Leia Organa in the undergrowth and pokes her with a spear. What follows is several minutes of two characters with no shared language working out that neither is a threat — no subtitles, no translation, played almost entirely on performance inside a suit. It is the reason the Ewoks land as people rather than as mascots, and the film needs them to land, because the entire third act depends on the audience accepting that they can beat the Empire.
The military point
The Battle of Endor is won on the ground by a pre-industrial society using logs, rocks and knowledge of terrain against armoured infantry and walkers. This is the trilogy's closing argument, and it is not subtle: the Empire loses because it does not consider the locals worth planning for.
Beyond the film
Warwick Davis reprised him in the two Ewok television films, Caravan of Courage (1984) and The Battle for Endor (1985), and returned to the role decades later in The Rise of Skywalker (2019), making Wicket one of very few characters played by the same performer across thirty-six years.