Emperor Ali Swan is an anthropomorphic swan.
The middle-aged Ali Swan is the Emperor of the small foreign country of Alistan. Rather than an idle nobleman, Ali Swan is also a skilled businessman who serves as CEO of Alistan's most thriving industry, the culture and exportation of a special variety of avocados. Tricky if not outright villainous, Swan once sent Scrooge McDuck an elephant as a "gift", knowing full well that the capricious animal could only be fed with great quanitties of Swan's own avocados.
Behind the scenes
Ali Swan only ever appeared in The Costly Cat.
In spite of the identical family name, it is unlikely that Ali Swan is related in any way to Janitor Swan, Cissy Swan or Susiebelle Swan.