 Mycenaean armies shared several common features with other significant Late Bronze Age powers : they were initially based on heavy infantry , which bore spears , large shields and , in some occasions , armor . Later in the 13th century BC , Mycenaean warfare underwent major changes both in tactics and weaponry . Armed units became more uniform and flexible , while weapons became smaller and lighter . The spear remained the main weapon among Mycenaean warriors until the collapse of the Bronze Age , while the sword played a secondary role in combat . 
