That would be a no to military parades, but displays of power were almost expected during significant events in the Middle Ages, such as coronations, funerals and the formal entries into cities.

Armies were not the focal point of such pageantry: the personal authority of the monarch would be emphasised. (Also, armies were raised in times of war, so to have a standing army was extremely expensive, ceremonies were pricey but probably cheaper in the long run!) The most well-researched pageantries are probably the Joyous Entries of the Low Countries/Burgundy. These events were a ritualised form of entering the city, where a ruler would assert his power over the citizens, and mutual oaths of protection and loyalty would be exchanged.

'Self-Representation of Court and City in Flanders and Brabant in the Fifteenth and Early Sixteenth Centuries' by Wim Blockmans and Esther Donckers covers many aspects of asserting public power (and it's open access so available online!)