' s ▁flag ▁as ▁the ▁national ▁war ▁flag . ▁ ▁Bel gr ano ▁then ▁went ▁on ▁a ▁diplom atic ▁mission ▁to ▁Europe ▁along ▁with ▁Bernard ino ▁Riv ad avia ▁to ▁seek ▁support ▁for ▁the ▁revolution ary ▁government . ▁He ▁returned ▁in ▁time ▁to ▁take ▁part ▁in ▁the ▁Congress ▁of ▁T uc um án , ▁which ▁declared ▁ ▁Argent ine ▁Independ ence ▁( 1 8 1 6 ). ▁He ▁promoted ▁the ▁In ca ▁plan ▁to ▁create ▁a ▁constitution al ▁mon archy ▁with ▁an ▁In ca ▁desc endant ▁as ▁Head ▁of ▁State . ▁This ▁proposal ▁had ▁the ▁support ▁of ▁San ▁Martín , ▁Martín ▁Miguel ▁de ▁Gü emes , ▁and ▁many ▁provincial ▁deleg ates , ▁but ▁was ▁strongly ▁rejected ▁by ▁the ▁deleg ates ▁from ▁Buenos ▁Aires . ▁The ▁Congress ▁of ▁T uc um án ▁approved ▁the ▁use ▁of ▁his ▁flag ▁as ▁the ▁national ▁flag . ▁After ▁this , ▁Bel gr ano ▁again ▁took ▁command ▁of ▁the ▁Army ▁of ▁the ▁North , ▁but ▁his ▁mission ▁was ▁limited ▁to ▁protect ing ▁San ▁Miguel ▁de ▁T uc um án ▁from ▁royal ist ▁adv ances ▁while ▁San ▁Martín ▁prepared ▁the ▁Army ▁of ▁the ▁And es ▁for ▁an ▁alternative ▁off ensive ▁across ▁the ▁And es . ▁When ▁Buenos ▁Aires ▁was ▁about ▁to ▁be ▁inv aded ▁by ▁José ▁Ger vas io ▁Art ig as ▁and ▁Est an is la o ▁López , ▁he ▁moved ▁the ▁Army ▁south wards , ▁but ▁his ▁troops ▁mut in ied ▁in ▁January ▁ 1 8 2 0 . ▁Bel gr ano ▁died ▁of ▁dro ps y ▁on