None, brown feathers
Prof. Gaviancio (grandfather)
Base of operations:
Emil Eagle is the evil genius that either steals inventions from Gyro Gearloose or uses his inventions to steal from others. He often works with the Beagle Boys to steal Scrooge McDuck's money and he has teamed up with other villains like Black Pete and The Phantom Blot.
Uncle $crooge #63 (1966)
Country of origin:
Emil Eagle as I have drawn him here is not the way he looked in the beginning. In his first appearance he looked more like a vulture with pale skin and some white feathers on the back of his head. His got his current appearance in Walt Disney Comics #330 in 1968, which he has kept even though his feathers have been show as white on occasions. The white feathers could be a mistake like Magnus Robot Fighter getting white boots (Russ Manning didn't specify that the leather boots should be brown because he thought it would be evident that leather boots should be brown and the colorist thought no specified color meant they should be white). Mistakes in coloring were quite common at the time. The most famous example is the Hulk who started out as grayish green in the first issue and became his well-known green color in #2 because of a mix-up in the coloring.
Emil Eagle was quite popular as a villain for Gyro Gearloose and Supergoof in the sixties and seventies, but apparently his popularity diminished up thru the eighties. From 1993 to 2004 Emil Eagle only appeared in one story and unlike most of Disney's cast of characters he has not appeared in cartoons or any other media. As comic book characters rarely vanish permanently he will presumably reappear at some point.