Gauis marius also re-invented the pilum. He was the one that thought of the bright idea of making the pilum stick to the enemy (having the end bend on impact). Another mistake by CA.
Equittes were the 1st class of the roman world. They were provided a public horse payed for by the state. After a while they ceased to be a effective force and were replaced by gauls-greeks.
You also forgot to mention in the beginning that before the marian reforms. Only people that owned a certain amount of land could join the army. What marius did was he allowed the head count (lowest of the low class) to be recruited, because they have no money the state provides the weapons and armor. Marius probaly argued that after they got released, because they were so poor they would be a danger to society. So he also gave a piece of land to veterans after campaigns.
"the people weren't satisfied with the citizen-army anymore."
The people and senate were very much satisfied with the citazen army. Marius did it out of neccasity. Rome at that time got beaten in battle aplenty and the number of land-owning male citazens was running low. He probaly had to argue against blue in the face senators.
Bookmarks