In 694 B.C. the ruler of Lu (also of the imperial clan) married a Ts'i princess, who, as has been stated in Chapter XXXIV., not only had incestuous relations with her brother of Ts'i, but led that brother to procure the murder of her husband. In connection with this woman's further visit to Ts'i two years later, the rule is cited: "Women, when once married, should not recross the frontier." The same rule is quoted in 655 when a Lu princess, who had married a petty mesne-vassal of Lu in 670, recrossed the Lu frontier in order to visit her son in Lu. The Second Protector, during his wanderings, we know, married first a Tartar wife and then a Ts'i wife, both of whom showed disinterested affection for him, and genuine regard for his rights to the Tsin succession, Yet the ruler of Ts'in supplied him with five more royal girls, of whom one had already been married to the Second Protector's predecessor and nephew, the Marquess of Tsin. It is but fair to the memory of this uxorious Tsin ruler to say that he only took her over under protest, and under the immediate stress of political urgencies; he ultimately made her his principal spouse at the expressed desire of his ally the Ts'in ruler. He must have later married a daughter of the Emperor too, for, after the succession of a son and grandson, another of his sons named "Black Buttocks," being the youngest, and also "son of a Chou mother," came to the throne. Thus in those troublous times the honour of imperial princesses evidently did not count for very much at the great vassal courts. The readiness of Ts'in to induce the Tsin ruler to take over his nephew's wife (being a Ts'in princess) accentuates the semi-Tartar civilization of Ts'in at least, if not of Tsin too; for both Hiung-nu (200 B.C.) and Turks (A.D. 500) had a fixed rule that a Khan successor should take over all his predecessor's women, with the single exception of his own natural mother. In the year 630 the King of Ts'u married or carried off two CHÊNG sisters (of the imperial clan). The ruler of CHÊNG had been insolent to the future Second Protector during his wanderings in the year 637, and, in order to avoid that Protector's vengeance, had been subsequently obliged to throw himself under Ts'u protection. "This ignoring of the rites by the King of Ts'u will result in his failing to secure the Protectorship," it was said. However, these princesses, though of the imperial _Ki_ clan by marriage into it, were really daughters of a CHÊNG ruler by two separate Ts'i and Ts'u wives: moreover, previous to the accession of the Hia dynasty (in 2205 B.C.), a Chinese elective Emperor had married the two daughters of his predecessor, whose own son was unworthy to succeed: and, generally, apart from this precedent, the rule against marrying two sisters, even if it existed, seems to have been loosely applied (_cf._ Chapter XXXIII.).