Battle of Leipzig

‘…The battle commenced on the southern side, at daybreak of the 16th. The Allies charged the French line there six times in succession, and were as often repelled. Napoleon then charged in his turn, and with such effect, that Murat's cavalry were at one time in possession of a great gap between the two wings of the enemy. The Cossacks of the Russian imperial guard, however, encountered the French horse, and pushed them back again. The combat raged without intermission until nightfall: three cannon shots, discharged at the extremity of either line, then marked as if preconcertedly, the pause of battle; and both armies bivouacked exactly where the morning light had found them. Such was the issue on the south, where Napoleon himself commanded. Marmont, his lieutenant on the northern side, had been less fortunate. Blucher attacked him with a vast superiority of numbers: nothing could be more obstinate than his defence; but he lost many prisoners and guns, was driven from his original ground, and occupied, when the day closed, a new line of positions, much nearer the walls of the city.
Gallant as the behaviour of his troops had been, the result satisfied Napoleon that he must finally retreat from Leipsig; and he now made a sincere effort to obtain peace…’

The description above, of the Battle of Leipzig (began October 16, 1813), comes not from Walter Scott, but from son-in-law, John Gibson Lockhart, in his “The History of Napoleon Buonaparte”.  What must have been a friendly competitive situation, with both men working in the same sphere, certainly seems to have fueled the enthusiasm and creativity of each.  The introduction to Lockhart’s history, published two years after Scott’s “Life of Napoleon Buonaparte” compares the two:

‘…One recalls at once what he said of "the lofty impartiality" with which Sir Walter Scott had written of Napoleon before him, and with which he appears to have faced his lesser task. As a biography, as a writing of history, as an example of historic style, Lockhart's comparatively modest essay must be called a better performance than Scott's. But "the real Napoleon" has not yet been painted.
Lord Rosebery, in his book on Napoleon: the Last Phase, asks if there will ever be an adequate portrait? The life is yet to be written that shall profit by all the new material that has come to light since Scott wrote his nine volumes in 1827, and Lockhart published his in 1829. But Lockhart's book has still the value of one written by a genuine man of letters, who was a born biographer, and one written while the world-commotion of Napoleon was a matter of personal report. It is tinged by some of the contemporary illusions, no doubt; but it is clearer in its record than Scott's, and while it is less picturesque, it is more direct.

His comparative brevity is a gain, since he has to tell how, in brief space, "the lean, hungry conqueror swells," as Lord Rosebery says, "into the sovereign, and then into the sovereign of sovereigns."
In view of the influence of the one book upon the other, and the one writer upon the other, it is worth note that Lockhart had a fit of enthusiasm over Scott's Napoleon when it first appeared, or rather when he first read the first six volumes of the work, before they were "out," in 1827. He thought Scott would make as great an effect by it as by any two of his novels. This proved a mistaken forecast, but Scott was paid an enormous price—some eighteen thousand pounds. When then John Murray, who had already co-opted Lockhart as his Quarterly editor, thought of inaugurating a "Family Library," and he proposed to his editor this other Napoleon book, it must have seemed in many ways a very attractive piece of work. But owing partly to Lockhart's relations with Scott, and partly to the need of avoiding any literary comparisons, these small, fat duodecimos appeared anonymously. That was, as it has been already mentioned, in 1829, two years after Scott's book…’

Frederick Augustus I of Saxony

Frederick Augustus was born in Dresden; December 23, 1750. Saxony became a kingdom (December 11, 1806) following the dissolution of the Holy Roman Empire under Napoleon's Confederation of the Rhine (July 12, 1806). The confederation was formed after Napoleon defeated the forces of the Holy Roman Emperor Francis II at the Battle of Austerlitz. Frederick Augustus thus served as Elector of Saxony, as part of the HRE, and King of Saxony under the Rhine Confederation.

Scott covers Frederick Augustus in his "Life of Napoleon Buonaparte". The Battle of Leipzig (October 16-19, 1813) in Saxony proved very costly to Napoleon. Though he ultimately prevailed over German forces, this battle was a prelude to his abdication and exile in Elba. Per Scott, Napoleon appreciated Frederick's character:

"...Perhaps also, Napoleon might be influenced by the feeling of what was due to the confidence and fidelity of Frederick Augustus of Saxony, who, having been so long the faithful follower of his fortunes, was now to be abandoned to his own. To have set fire to that unhappy monarch's city, when leaving him behind to make terms for himself as he could, would have been an evil requital for all he had done and suffered in the cause of France..."