At what time was the most different kinds of armour in use at the same? Perhaps and odd question, but let me evaluate:

In the early middle ages (viking age-ish) the upper limit of armour seems to have been chainmail and those who couldn't afford it would just have a shield.

When we get to the late middle ages (think late war of the roses) everyone from knights to infantrymen seem to have worn plate armour, though to different degrees.

Was there ever a time where some soldiers on a battlefield would have fought in full plate, others ln chainmail, still others in leather or cloth armour and others still just a shield. When if so?