Also difference of race is a cause of faction, until harmony of spirit is reached; for just as any chance multitude of people does not form a state, so a state is not formed in any chance period of time. Hence most of the states that have hitherto admitted joint settlers or additional settlers6 have split into factions; for example Achaeans settled at Sybaris jointly with Troezenians, and afterwards the Achaeans having become more numerous expelled the Troezenians, which was the Cause of the curse that fell on the Sybarites; and at Thurii Sybarites quarrelled with those who had settled there with them, for they claimed to have the larger share in the country as being their own, and were ejected; and at Byzantium the additional settlers were discovered plotting against the colonists and were expelled by force of arms; and the people of Antissa8 after admitting the Chian exiles expelled them by arms; and the people of Zancle9 after admitting settlers from Samos were themselves expelled; and the people of Apollonia on the Euxine Sea after bringing in additional settlers fell into faction; and the Syracusans after the period of the tyrants conferred citizenship on their foreign troops and mercenaries and then faction set in and they came to battle; and the Amphipolitans having received settlers from Chalcis were most of them driven out by them.
Politics Book 5
The whole thing is interesting and applicable to the US; a reminder that human nature doesn’t change.
‘Almost all the other subjects which we intended to treat  have now been discussed. There must follow the consideration of the questions, what are the number and the nature of the causes that give rise to revolutions in constitutions, and what are the causes that destroy each form of constitution, and out of what forms into what forms do they usually change, and again what are the safeguards of constitutions in general and of each form in particular, and what are the means by which the safeguarding of each may best be put into effect.’