The Bedouins appear in Uncharted 3: Drake's Deception. They are a desert dwelling Arab ethnic group, led by Salim.
Uncharted 3: Drake Deception
When Nathan Drake was pinned down in the desert settlement by Katherine Marlowe's agents, the Bedouins rode in to dispose of them. Salim spared Drake's life, and they rode out together.
The day after, the Bedouins and Salim help Drake rescue Victor Sullivan from the enemy caravan. They succeed, but the Bedouins are separated from the pair in the sandstorm whilst searching for Ubar.
As well as Salim, three of the Bedouins are available as multiplayer skins. These are: