/usr/share/fonts/X11/misc/fonts.alias is the culprit and needs to be updated with modern UCS / UTF8 / UTF-8 / ISO10646-1 alias defaults.
The problem is that this file specifies as default font alias, for example: 6x10 -misc-fixed-medium-r-normal--10-100-75-75-c-60-iso8859-1 Note the "iso8859-1" char set - which according to wikipedia https://en.wikipedia.org/wiki/ISO8859-1 contains only 191 characters, whereas iso10646 https://en.wikipedia.org/wiki/ISO10646 contains up to 128,000 characters. The head of the above file dates it to circa 2000. Back then, UTF-8 support was probably thin on the ground, and defaulting the fonts to iso10646 may have caused problems. But today this is not the case, so this bug should probably be fixed by changing the default character sets for fixed font aliases, from iso8859-1 to iso10646-1. In the meantime, a workaround in X is to manually specify your font, for example as follows: xterm -fn "-misc-fixed-medium-r-normal--10-100-75-75-c-60-iso10646-1" and optionally if needed (don't know sorry), also specify the same font for your bold font: ... -fb "-misc-fixed-medium-r-normal--10-100-75-75-c-60-iso10646-1" It would certainly be preferable to just call, e.g.: uxterm -fn 6x10 -fb 6x10 I guess if this would possibly cause problems for some people (really everyone SHOULD be using utf8 by now, and at the very least the default should all be utf-8 by now), then additional alias could be included in the fonts.alias file above, e.g.: 6x10utf8 -misc-fixed-medium-r-normal--10-100-75-75-c-60-iso8859-1 or perhaps 6x10iso10646 -misc-fixed-medium-r-normal--10-100-75-75-c-60-iso8859-1 etc This is a generic xterm / uxterm problem, affecting vim, mutt etc, and not just emacs.
