The eastern kingdoms, for example the Ptolemaic, Seleucid, Graeco-Bactrian and Indo Greek kingdoms, had an even more problematic situation. The basis of their militaries relied on Greeks, which were obviously not common to the areas that they ruled over. In order to overcome this, these kingdoms set up military colonies, known as Klerouchoi, to settle mercenaries and others from Greece. The system would allow for the colonists to be given a plot of land and in return they would provide military service when needed. In Ptolemaic Egypt, for example, soldiers and officers were given lots 'in exchange for military service, whenever needed'. W.W. Tarn even suggests that the Greek (known to the Indians as 'Yavanas') population in India may not have been as small as one would suppose, stating 'there may well have been many more Yavanas...than we should suppose; we may have to reckon with a considerable number of men, adventurers or mercenaries from the west'.