The exaltation of the South German dynasties had long been a favourite project with Napoleon, who saw in the hatred of the House of Bavaria for Austria a sure basis for spreading French influence into the heart of Germany.  Not long after the battle of Austerlitz, the Elector of Bavaria, while out shooting, received from a French courier a letter directed to “Sa Majeste le Roi de Baviere et de Suabe."[63] This letter was despatched six days after a formal request was sent through Duroc, that the Elector would give his daughter Augusta in marriage to Eugene Beauharnais.  The affair had been mooted in October:  it was clinched by the victory of Austerlitz; and after Napoleon’s arrival at Munich on the last day of the year, the final details were arranged.  The bridegroom was informed of it in the following laconic style:  “I have arrived at Munich.  I have arranged your marriage with the Princess Augusta.  It has been announced.  This morning the princess visited me, and I spoke with her for a long time.  She is very pretty.  You will find herewith her portrait on a cup; but she is much better looking.”  The wedding took place at Munich as soon as the bridegroom could cross the Alps; and Napoleon delayed his departure for France in order to witness the ceremony which linked him with an old reigning family.  At the same time he arranged a match between Jerome Bonaparte and Princess Catherine of Wuertemberg.  This was less expeditious, partly because, in the case of a Bonaparte, Napoleon judged it needful to sound the measure of his obedience.  But Jerome had been broken in:  he had thrown over Miss Paterson, and, after a delay of a year and a half, obeyed his brother’s behests, and strengthened the ties connecting Swabia with France.  A third alliance was cemented by the marriage of the heir to the Grand Duchy of Baden with Stephanie de Beauharnais, niece of Josephine.

In the early part of 1806 Napoleon might flatter himself with his brilliant success as a match-maker.  Yet, after all, he was less concerned with the affairs of Hymen than with those of Mars and Mercury.  He longed to be at Paris for the settlement of finances; and he burned to hear of the expulsion of the Bourbons from Naples.  For this last he had already sent forth his imperious mandates from Vienna; and, after a brief sojourn at the Swabian capitals, he set out for Paris, where he arrived incognito at midnight of January 26th.  During his absence of one hundred and twenty-five days he had captured or destroyed two armies, stricken a mighty coalition to the heart, shattered the Hapsburg Power, and revolutionized the Germanic system by establishing two Napoleonic kingdoms in its midst.