Although Celtic lettering evolved on its own and prompted different calligraphic styles after the crusades, elements of the Arabic influence survived with it, its appeal remaining evident to this very day. For instance, this kind of lettering is very similar to the one Louis Tiffany used to make the most recognizable athletic insignia in North America - the New York Yankees logo, which is now over 110 years old, and has inspired hundreds of spin-offs in many athletic and non-athletic fields all over the world.
The original character set made by Kausche was quite minimal, consisting of only numerals and uppercase letters along with a few alternates. But in this digital version the set has been considerably expanded into uppercase, lowercase, numerals, punctuation, a complete set of accented characters, and more than 15 alternate letters built into the font.
Sultan is a great font choice particularly for design contexts of fantasy, middle ages legend, mystical and new age content, pirate literature, and Irish history. But it is also an excellent all-purpose display and poster font in general.