Changes

Although the first professional armies were likely founded in the 3rd millennium BC, what we can see is that by the 2nd millennium BC the use of foreigners and , elite soldiers , and officers were used within military units. Increasingly throughout By the 2nd millennium BC, warfare was also happening in increasingly diverse places, including war conducted by navies as they battles to control important sea lanes and trade or communication routes. By the first half of the 1st millennium BC, armies became more consistently professional with full time soldiers and specialized troops. Another important development was the infrastructural developments that facilitated the movement and equipping armies, including roads and armories. This professionalization facilitated warfare by not making it bound by the agricultural cycles that would have limited when armies could fight. Another important development was the infrastructural developments that facilitated the movement and equipping armies, including roads and armories. This also enabled far larger empires to now emerge in the Old World, starting first with the Neo-Assyrian Empire and continuing to the Roman and even later empires. The success of creating professional armies, consisting of foreign volunteers and mercenary forces, and having specialized units of officers was first developed by the Assyrians with later states building upon the Neo-Assyrian system. The Roman system perhaps represents an apogee of the developed ancient armies, where armies were now permanently based in distant provinces. However, this system built on the critical foundations laid down from the 3rd to early 1st millennium BC.