In 55 bc julius caesar's roman army invaded england, landed in kent and marched north west until it reached the broad river thames at what is now southwark. There were a few tribes men living on the opposite bank but no major settlement. However, by the time oc the second roman invasion 88 years later, a small port and mercantile community had been established there. The their administrative headquarters on the north bank, calling it londinium a version of its old celtic name