I’m Mary Poppins y’all is a line quoted from the fictional character Yondu, who utters the sentence during one scene of the 2017 movie Guardians of the Galaxy Vol. 2.
The line has become popular among fans of the Guardians of the Galaxy franchise. This popularity has eventually led to the birth of various art and memes themed around the quote.
Mary Poppins is originally the name-giving character from the 1964 Disney movie Mary Poppins.
The Marvel sci-fi action film Guardians of the Galaxy Vol. 2 (released in 2017) made a reference to that movie in one of its scenes. During the scene, we can see Yondu (played by Michael Rooker) flying next to Peter Quill (played by Chris Pratt), who tells him that Yondu resembles Mary Poppins.
Yondu then screams in excitement: “I’m Mary Poppins, Y’all!”
The meme became almost instantly popular after the film’s release. The early memes featured Youndu’s figure photo-edited onto Mary Poppins artworks.
Later Michael Rokker also played a key part in popularizing the I’m Mary Poppins y’all phenomenon, by sharing the memes surrounding the topic on his Instagram page and by making references to it himself.