Persian Invasion is a modification for Rome - Total War 1.5 that begins in 490BC. The vast Persian Empire celebrates a golden age of prosperity, and looms over the smaller states that surround it. The king of Persia, Darius the Great, is a tolerant leader, but he has not forgotten what happened in Ionia, and may yet seek revenge for Greek treachery...
As seen in Persian Invasion
Celtic light cavalry are lightly armored and carry spears and shields. They are best used as scouts and in pursuit of fleeing enemies, and ride sturdy, sure-footed ponies with a good turn of speed. Like many barbarian warriors, however, they can lack battle-discipline and be over-keen to enter battle against worthy opponents. Honor and standing come from fighting, and sometimes the urge for glory overwhelms good sense! These men are all good fighters, but find organized, formal warfare goes against the grain. They are unlikely to be very effective against steady infantry unless attacking from an unexpected direction.