The Myceneans had acropoleis. The fortification of these becomes more prominent in the later period, but the phenomenon of the acropolis definitely goes back to the Bronze Age. In fact, a type of 'acropolis' can be seen in many neolithic communities, like the Ukrainian megasites or some of the Near Eastern and Balkan 'tell' sites, as well.
Bintliff in 'An Archaeology of Greece' calls particularly the late Mycenean sites 'acropolis', but also notes that the fortification aspects are generally late Mycenean and not always an original element, in contrast to the 'palace economies' of Minoan or Early Mycenean Greece. However, the acropolis phenomenon does go further back on the Greek mainland, such as at Thebes.