Cavalry<span> are those soldiers who fought battles mounted on horseback. </span>Infantry<span> is the category of soldiers that fights on foot. </span>Artillery<span> is the large guns/cannons used for targeting enemy positions which are beyond the range </span>
I do not know which states but the main countries are China, India, Egypt, Greece, Rome and Britain.
It used oligarchy, rule by a few.
The Mexican Cession happened in 1848. In this treaty, Mexico handed over Texas to the US. Hope this helps.