Avengers: Age Of Ultron - 32 Easter Eggs, In-Jokes And References
19. Wakanda
It was only a matter of time before Wakanda actually became a setting for action in the MCU, especially with Black Panther on its way as a stand-alone.
Unfortunately, there was no cameo for the Wakandan prince, but his kingdom does play a major part in the narrative when Ultron's plan hinges on the need to source a significant amount of Vibranium. He finds out that the twins are aware of a former ally of Von Strucker's, who might be the answer (at the same time as the Avengers do).
Stark realises he recognises the name of the smuggler Ultron is seeking - Klaue - having been someone he'd met before at an arms dealing convention, who was based off the coast of Africa, who knew more than most about Wakanda's vibranium stock (having been branded in Wakandan as a "thief").