In which country did mulligatawny soup originate?

Mulligatawny is a soup which originated from South Indian cuisine.

Mulligatawny was very popular in British India by the end of the 18th century, and by the 1800s it began to appear in cookbooks of the day; with each cook (or cookbook) featuring its own recipe. Recipes for mulligatawny varied greatly at that time and over the years (e.g., Maria Rundell's 'A New System of Domestic Cookery' contained three versions), and later versions of the soup included British modifications that included meat (though the local Madras recipe on which it was based did not). Early references to it in English go back to 1784.