Equites (plural of the Lat. eques, horseman), or knights, an order of the people in ancient Rome, which in some respects may be compared with the English gentry. Their origin is attributed by Roman historians to the institution of Romulus, who is said to have selected the first 300 out of the three chief divisions of the patricians, and to have divided them into three centuries, named Ramnenses, Titienses, and Lucernes, corresponding to similar names of the three patrician tribes. Tarquin the Elder added three new patrician centuries, and Servius Tullus 12 new ones from among the richest plebeians. They formed a regular military body, being obliged to serve on horseback in time of war, and were divided into turmoe of 30 men each, subdivided' into tens. They were also called celeres, and their chiefs tribuni celerum. Politically they seem to have represented an aristocracy of wealth in opposition to the aristocracy of birth, particularly after they became a distinct body of the people by the institutions of Servius Tullius. Under the republic the knights were enrolled by the censors and consuls for a service of five years, being supplied by the state with a largo sum for the purchase, equipment, and maintenance of a horse, but with no personal pay.

Every dictator, immediately after his appointment by the senate, had to select a commander of the horse, called magister equitum. During service they had no votes in the assemblies of the centuries. At the time of the siege of Veii, when the want of cavalry was much felt by the Romans, a new body was added to the ancient knighthood, consisting of a large number of young volunteers who offered to enter the ranks at their own expense. The new knights received regular pay, but had no vote, and no share in many distinctions enjoyed by the old order. Gradually they coalesced into a numerous and wealthy middle class, placed politically and socially between the patricians and plebeians, and were so recognized by a law of Caius Gracchus (123 B. 0.). Of the privileges as jurymen which the same laws bestowed upon them, they were deprived by Sulla. At that period they were generally the farmers of the public revenues, under the name of publi-cani, and as such seem to have been despised by the Roman people. Under the empire, owing to the heterogeneous elements of which their increased body was composed, they gradually sank, and in spite of efforts to restore their influence they disappeared from political life under the later emperors.

In general the history of the Roman knighthood, as a political institution, is involved in great obscurity.