11th, 1624.

"I go on with my work _Of the law of nations_: if it may be of use to the world it is to you posterity will owe the obligation, since you made me undertake it, and assisted me in it." In the preliminary discourse he sets forth his motives for treating this subject.

"Many strong reasons determined me to write at this time.
I have observed in all parts of the Christian world such an unbridled licentiousness with regard to war as the most barbarous nations might blush at: they fly to arms without reason, or on frivolous pretexts; and when they have them once in their hands they trample on all laws human and divine, as if from that time they were authorised, and firmly resolved to stick at no crime." Thus it was from a principle of humanity that he composed this great work; and, as he writes to Crellius[148], to shew how unbecoming it was for a Christian and a reasonable man, to make war from caprice: which was too much practised.
In the dedication of this book to the King the author observes, that Lewis XIII.

like a propitious constellation, not satisfied with relieving the misfortunes of princes and protecting nations, had graciously supported him under his afflictions.

He presented his book to the King and the principal nobility; who, he writes to his brother[149], received it very graciously, but made him no return.