9 4 ▁BC , ▁a ▁ple be ian ▁trib une ▁always ▁pres ided ▁over ▁the ▁Ple be ian ▁C uri ate ▁Assembly . ▁This ▁" P le be ian ▁C uri ate ▁Assembly " ▁was ▁the ▁original ▁Ple be ian ▁Council , ▁which ▁elected ▁the ▁ple be ian ▁Trib unes ▁and ▁A ed iles , ▁and ▁passed ▁legisl ation ▁( ple b isc ita ) ▁that ▁applied ▁only ▁to ▁the ▁ple be ians . ▁ ▁From ▁ 4 7 1 ▁to ▁ 2 7 ▁BC ▁During ▁the ▁later ▁years ▁of ▁the ▁Roman ▁Kingdom , ▁King ▁Ser vi us ▁Tul lius ▁en act ed ▁a ▁series ▁of ▁constitution al ▁re forms . ▁One ▁of ▁these ▁re forms ▁resulted ▁in ▁the ▁creation ▁of ▁a ▁new ▁organiz ational ▁unit , ▁the ▁tribe , ▁to ▁assist ▁in ▁the ▁re organ ization ▁of ▁the ▁army . ▁Its ▁divisions ▁were ▁not ▁eth nic ▁( as ▁the ▁divisions ▁of ▁the ▁Cur ia ▁were ), ▁but ▁rather ▁ge ographical . ▁Tul lius ▁divided ▁the ▁city ▁into ▁four ▁ge ographical ▁districts , ▁each ▁en comp ass ing ▁a ▁single ▁tribe . ▁Between ▁the ▁reign ▁of ▁Tul lius ▁and ▁the ▁late ▁ 3 rd ▁century ▁BC , ▁the ▁number ▁of ▁tribes ▁expanded ▁from ▁ 4 ▁to ▁ 3 5 . ▁By ▁ 4 7 1 ▁BC , ▁the ▁ple be ians ▁decided ▁that ▁organization ▁by ▁tribe ▁granted ▁them ▁a ▁level ▁of ▁political ▁independence ▁from ▁their ▁pat ric ian ▁pat rons ▁that ▁the ▁cur iae ▁did ▁not . ▁Therefore , ▁around ▁ 4 7