What are soldiers that are paid in Persia?

In ancient Persia, soldiers who were paid were known as "sparabara" or "immortals." The sparabara were part of the infantry, often equipped with shields and spears, while the Immortals were an elite unit of 10,000 soldiers who formed the backbone of the Persian military. These paid troops played a crucial role in maintaining the stability and expansion of the Persian Empire. Their compensation often included land, provisions, and other benefits, reflecting the importance of a well-supported military in Persian society.