From my point of view it was created by gurudev RNT for Englishman. They included only those boundries of India which were under British Emperor. Without understanding the meaning of that song we are simply following what our's senior were following. Please check
Jana gaṇa mana adhināyaka jaya he For that time ruler
Bhārata bhāgya vidhātā
Punjāba Sind Gujarāṭa Marāṭhā ONLY INCLUDED THOSE BOUNDRIES
Drāviḍa Utkala Banga
Vindhya Himāchala Yamunā Gangā NO OTHER RIVER BUT WE HAVE MORE THAN THESE
Ucchala jaladhi taranga
Tava śubha nāme jāge
Tava śubha āśiṣa māge
Gāhe tava jaya gāthā
Jana gaṇa mangala dāyaka jaya he
Bhārata bhāgya vidhāta WHO
Jaya he jaya he jaya he
Jaya jaya jaya jaya he!

???????????????????????????????????????????? THIS ITSELF HAS SMELL OF GULAMI