Pieter Geerkens is making a good point in the comments: a knight was usually supposed to lead a small unit from his manor/castle/etc. Besides the knights or semi-professional soldiers there could be carriers, helpers, servants, etc. moving with the army. An inportant point about the answer: As the call to arms was often periodic or even annual, it would make more sense if usually his subordinates were the same people and not random totally untrained peasants.
I will illustrate this with XIII c music (unfortunately not early middle ages)
This page has commented lirics of the music 'O que da guerra levou cavaleiros' composed by the king Alfonso X. His basic idea was to ridicule the knights who did not fulfill their feudal contract in wartime. Each verse ridicules a specific case (and some historians believe that each verse really correspond to an specific knight). So, let's see how the king was displeased with some of his knights:
O que tragia o pendom sem oito
The one who brought his banner without eight (without his 8 promised companions)
e a sa gente nom dava pam coito
and to his people did not give baked bread
nom vem al maio
do not come to the May
O que tragia o pendom sem sete
The one who brought his banner without seven (without his 7 promised companions)
e cinta ancha e mui gram topete,
and a large belt and well combed hair
nom vem al maio.
do not come to the May
Up to now we have 2 verses about knights who showed up with no companions. The King made them the favor of specifying in the music exactly the number of expected soldiers - besides telling everybody about their greed and vanity.
O que tragia o pendom sem tenda,
The one who brought his banner without tent
(without his military tent and equipment for long term stay. Was he supposing the war would be quick?)
per quant'agora sei de sa fazenda,
considering what I know now about his situation
(probably the King got word that he was rich enough to pay for his equipment)
nom vem al maio.
do not come to the May.
Now the king ridicules another greedy or coward knight who did not bring equipment to stay for the whole annual campaign.
About the 'do not come to the May': It means the feasts of May, a merry party time also including religious Marian feasts. It also means the period when the army must assemble to the main annual campaigns. So telling them not to come to the May means that they do not deserve neither to party and pray with the King nor to fight with the army.
A good moral of this history is 'do not try to fool a King-poet': he will shame you in music for the ages...
PS: If you wonder about the language it is Galician-Portuguese - it is surely not modern Portuguese, so forgive me any mistakes in translation. Comment if you know better.