The yellow Shiba Inu everyone was Dogeifying turns out to be from a real picture of a real dog by the name of Kabosu! The puppy was saved by Japanese kindergarten teacher Atsuko Sato.

Kyle Chayka has the full story at The Verge, and here's to sum things up. Sato adopted Kabosu in 2008 and started posting the dog's pictures to her blog to raise awareness of puppy mills and pet adoption.

In 2010, she uploaded the fateful snap of Kabosu reclining on a couch and gazing at the camera, which may have started the Internet practice of posting pictures of Shiba Inus on the Internet.

Chayka recounts the evolution of the meme:
Doge began as a string of seemingly random web phenomena. In October, 2010, the word popped up on Reddit with a popular post of a corgi photo titled "LMBO LOOK @ THIS FUKKIN DOGE." As doge became synonymous with silly dog photos, the meme's multicolored Comic Sans script evolved from the Tumblr Shiba Confessions, which launched in September, 2012 and described its mission as "funny text in Comic Sans over unrelated pictures of Shibas."