It has already been mentioned that in ancient time Bhutan seems,occasionally atleast,to have formed part of the kingdom of Kamrup.The historian of Mir Jamulah’s invasion in the middle of the seventeen century says that the people of that country spoke a dialect allied to that of the Koches.
After expelling Nar Singh ,Malla Dev ascended the throne and assumed the name Naranarayan.He appointed his brother Sukladhvaj to be his Commander-in-Chief.In this capacity Sukladhvaj displayed such dash and rapidity of movement that he was nickname Silarai,or the Kite King.In Assam we organized the Silarai Dibokh.And now-a-days our Government decleared it as a Holiday.
War with Ahoms:-Nar Narayan soon come into conflict with the Ahoms.The cause of quarrel is uncertain.According to one authority,the Ahom king Suklemmung was the aggressor.A petty chief,or Bhuiya,conprired,it is said,against Nar Narayan and,on detection,field to Suklmmung,who gave him shelter and made an unsuccessful attack on the Kochs kings.However that may be,in 1546 an expedition under Sukladhvaj was fought soon afterwas at Koliabar,on the opposite site of the Brahmaputra.
Construction of Gosain Kamal Road:-In this course of this operation ,the Koches constructed an embanked road the whole way from their capital in Koch Bihar to Naranarayanpur,in the south-west of what is now the North Lakhimpur subdivision,a distance of some 350 miles.The work was carried out under the supervision of Gosain Kamal,the Kings brother;part of its are still exist and known as Gosain Kamal’s road.
Victories over Jaintia,Tippera and Sylhet kings:-This great undertaking was completed in 1547 and the Koches then created a fort in Narayanpur..The kingdom of Jayantia was nexted attacked and,in the battle next followed,the Raja was killed by Chilarai with his own hand.His son was placed on the throne after promising to pay regular tribute.It is said that one of the condition imposed on him was that he should not in future strike Coins in his own name.This story received some confirmation from the fact that,until the year 1731,no kings of Jayantia appears to have recorded his name on the coins minted by him;on all knows coins of earlier date,as on most of the laters one also,the words ‘’rulers of Jayantia’’are used instead of the Raja’s name.
Chilarai,it is said,then proceeded to wages war against the Raja of Tippera,who was vanquished and put to death.His son was set up in his place and undertook to pay tribute to the extent of ten thousand rupees,one hundred gold mohars and thirty horses.There is no maintion of this war in the Tippers chronicles,and the only corroboration of the Kochs BANSAWALI is found in an Assamese Buranji of uncertain date.This is not sufficient to estlablish it as historical fact.
The Syleth king,it is alleged,was also defeated and slain,and his brother Asurai,who was nominated to succeed him,was fain to promise a tribute of a hundred elephants,two hundred horses,three lakhs of rupees and ten thousand gold mohars.This campaign,like the proceeding one,lacks confirmation,nor it is quite clear what part of Syleth is referred to.