<ctrl>-<shift>-p brings up the preferences dialog (or forth from the bottom in the left most menu, which is File<->Dosya > Inskscape Preferences<->Inskcape Secenekleri), then
Interface<->Interface then
Language (requires retart)
...then File > Quit<->Ciklis (bottom menu item), reopen and you are good to go.
I had the same problem. For anyone else stuck:
<ctrl>-<shift>-p brings up the preferences dialog (or forth from the bottom in the left most menu, which is File<->Dosya > Inskscape Preferences< ->Inskcape Secenekleri), then ->Interface then
Interface<
Language (requires retart)
...then File > Quit<->Ciklis (bottom menu item), reopen and you are good to go.