Cholas were the biggest dynasty in south india before kalabars invaded south india there where cheras cholas and pandyas not greatly extending their traditional teritory but since even in sangam age i.e before the kalabars during the reign of karikala cholan the madurai was captured and made as tribute paying soo even before kalabars chola dynasty is dominating and after kalabars again the medivial cholas rise to power during 9th centuary AD and they conquered both cheras amd pandyas and made a chola prince to be the viceroy of madurai(pandyas) and from 9th centuary to 13 centuary (400 yrs) cheras amd pandyas were under cholas control.even eastern chalukyas were completley under the cholas almost most of western chalukyas teritory were under chola( but not fully comquered) srilanka is completley under chola teritory and during the reign of rajendhira chola he expanded the chola teritory to peresnt day bengal where ganges has its delta soo he is called gangai konda cholan mean gangai=ganges, konda=captured chola is their name…….chola had a huge navy they conquered sri vijaya empire present day sumatra indonesia and the had an alliance with khmer kingdom with is near present day indonesia they had an great navy they crushed the chera navy at KANDALUR SALAI duringthe reign of raja raja chola (985–1014) since cholas jad sucha great army their foriegn campains were sucessful and they could conquer other kingdoms ouside of india hence the biggest dynasty in south india is cholas pandyas also had been big dynasty after the decline of later cholas 1255 A.D but it did not last long one for a centuary 1345(approx check wiki pedia) and they get lost to the invading muhgal forces led by maruthanayagam alais muhammed alif khan since chola maintained the huge teritories for a huge amount of time they are the biggest dynasty in south india