In the early 1670s, Frederick William supported Imperial attempts to reclaim Alsace and counter the expansion of Louis XIV of France. Swedish troops invaded Brandenburg in 1674 while the bulk of the elector's forces were in Franconia's winter quarters. In 1675 Frederick William marched his troops northward and surrounded Wrangel's troops. The elector achieved his greatest victory in the Battle of Fehrbellin; although a minor battle, it brought fame to the Brandenburg-Prussian Army and gave Frederick William the nickname "the Great Elector". After Sweden invaded Prussia in late 1678, Frederick William's forces expelled the Swedish invaders during the "Great Sleigh Drive" of 1678–79; Thomas Carlyle compared the wintertime Swedish retreat to that of Napoleon from Moscow.