Grotius was three times in France, each in widely contrasting circumstances. The first visit was in 1598–9, when at the age of fifteen he accompanied Count Justin of Nassau and Barneveld as one of the suite of these envoys from the States General of Holland to Henry IV. The second sojourn from 1621 to 1631, covers the period after his escape from prison at Loevestein, ten years spent, with the exception of the spring and summer of 1623, in Paris. The third from 1634 to 1645, is the period of his Swedish service, when he was Ambassador of Queen Christina to the Court of Louis XIII. Thus of the sixty-two years of Grotius’s life, one third was spent in Paris. It is the second of these French sojourns which now concerns us, for it was during this period that Grotius prepared and published his magnum opus, De Jure Belli ac Pacis.